What I love about this dude is he's a proper scientist but doesnt seem to realise it. He starts out by admitting his limitations and the limitations of his testing. Then he identifies, isolates, and carefully controls his variables one at a time. He enters the testing phase with a total open mind and considers everything regardless as to what his intuition might tell him. He carefully records his methods so others can try to replicate his results. He delivers his conclusions impassively by looking at the real outcome with no regard for any prior bias. Then he opens up his tests to a wider audience to invite their comments and review. Dude knows the scientific method inside out
Yeah except all the information is not clear because it doesn't say when this versus that, it only shows they are different and you cannot duplicate the results because it is not said nor clearly defined what difference is in progress on the one that is playing, only says what way they are different about the test then your left with , " . . . well oh shit now damn, i am must create all the tests for myself to achieve mine results this was all a teasing non pleasing non useful waste because it only showed me what i am already knew".
Funny thing is, in this video he's just confirming things that amp snobs have been saying all along, things like cab size matters, nitpicky things like that divider
@@jantje155 yeah and to me what follows from that is, if you like the sound of a particular cab from a particular company/place/time/country, the replicas or knockoffs might not be able to copy the sound perfectly. The interaction of the sound waves follows from the geometry in complex ways, and maybe the companies are only approximating the geometry and the small differences change the behaviour of the sound. But then again, maybe things average out in a way where small changes really don't have audible effects. Who knows! My bedroom has a specific resonant frequency that rings out when I hit a certain note on my guitar. It's possible that if a carpenter tried to create a replica of my bedroom, the resonance might be a bit different.
yup haha, thats because when you talk about electric guitars and tone wood, and all thats stuff doesnt matter, in question of the cabs, it affects more like acoustic guitars, more on how are they made not on what are they made of
@@xl000 I mean... Hyperbole is a thing. You obviously just want to have an argument about how you don't agree with his conclusions. Which is a discussion I couldn't care less about... Even if I tried really really hard.
@@xl000 The conclusions this video comes to are "these are the things that appear to empirically affect the sound a speaker box produces", the only way to disagree with this is to argue that all the testing and documentation was faulty and that none of his tests demonstrates any actual change in the output sound.
@@RockWonder210 fuck yeah make your own sound then have others looking to copy your shit. but build a box in a box so the fuckers don't know wahts up lol
The styrofoam cab has no business sounding that close to the Orange cab. This is hilarious. Cab makers have to be ripping their hair out at this. Excellent work. You conducted experiments exactly as one should, and were not afraid to say "this didn't affect the outcome as I hypothesized, so I moved on". Truly the mark of a mature experimenter. Well done.
@@crazyjack9voltbatteryamps How a speaker sounds in the room is far less important than how it sounds recorded. No one records room mics for records, no one hears the cab at live concerts, unless they are in a dive bar - it's all PA. This comparison does exactly what it's intended to do, if you feel it doesn't, make your own. Everyone can make their own decisions based on the information provided
@@remingtonlowe3992That's debatable.. If you like the sound you get in the room you'll play more. The sound you get when you're playing affects your choice of what you are creating at the time. Not everything played is going to be recorded either.
I don't think they're really ripping their hair out - most of the cost of cabs is just the speakers, which matches what he's saying. Then you have a bunch of parts and labor which are a much smaller percentage of that and then a fat margin (won't go into the full costing since that's a business class). It's probably like 30-60% depending on the company, with some of that percentage being brand value, but the idea is that the brand value is earned through quality (which is debatable over time and product revisions). Who should be ripping their hair out are audiophile collectors that try to sell or trade "grail" amps as though you can buy a sound (and thus the "skill" of a master lol) like an old violin.
The sad thing is though, that a LOT of guitar players will simply ignore all of his videos and cling on to their myths, maybe even double down and start attacking the integrity of these tests 🙄
A friend was demolishing 10 old electric organs. He wanted the amps inside. I said, wait, I want the speakers. And the reverb spring units. Have you ever built yourself a cheap guitar amp? What is it? An amp, a speaker and some scrap wood. I just got myself some free speakers, not top quality, still I can simply connect them to a small amp. For clean playing, a larger speaker is always okay. If you want distortion, things are a bit different. But hey, such projects are fun. And when you do your research too, chances are, you know what you are doing. And you learn on the go. Ever wondered why bass amps have 4 large speakers? Would that still work with 3 ones? And could a guitar amp get better, using 4 equal speakers?
@@voornaam3191 an old Bass player pal explained that it was all about air push. The larger the cone more flutter yet bassy and less articulate and Claritied. To push the same amount of air and tighten the clarity replace a 15 or 18 with 2 12's or even 4 10's etc. Or combine using a crossover.
This man is a genius. He does not fall for advertisement and "this is known", he experiments and learns himself. These videos will make so many "audiophiles" and audio companies really angry, since they clearly demystify all their mambo-jambo. The consumer on the other hand learns what really is important and where money is wasted or not. Very well done :)
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Not too scientific after all! 🙂
@@crazyjack9voltbatteryampsbut in the vast majority of cases, what we hear from a guitar amp/cabinet is what is recorded through the microphone placed in front of it. When we listen to our favourite songs on TH-cam, Spotify, CD, cassette, vinyl etc, that’s exactly what we are hearing. And when we are in a stadium listening to a band, the cabinet has a mic in front of it and, again, that is what we are hearing. He explains this in his video about amps. Why the “sound in the room” is actually kind of pointless to worry about.
@@crazyjack9voltbatteryamps well said. half of the info here is accurate but well known (eg. open and close back, size, arrangement etc). try to make a guitar from styrofoam and sell it as a boutique axe :) interestingly enough folks pay high dollars on guitars (when they can) and then they are convinced that cabs doesn't really matter... acoustics is a complex matter. or to look at it from a different angle: venues hire expensive acoustic engineers and designers to get the best and appropriate sound out of they rooms. the reason is the same. you can play and enjoy techno in a bunker but probably not other genres where proper sound really matters. no diss to techno venues ... oh wait, they design their rooms and use high quality speakers too to make the experience perfect :)
@@Jamiecb88Yes, but I think most people watching this video are players….. We are trying to get the best tone from where we’re standing on the stage which includes the air space around us. Way different than what the mic is picking up.
The acoustical principle that's causing the effect with making a hole or opening the back is called "helmholtz resonance". There is a caclulation to find the relationship between the boosting or cutting frequency and the size of the opening.
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Not too scientific after all! 🙂
@@crazyjack9voltbatteryampshis focus is on the close mic sound of the amp for the purposes of conventional recording. Obviously it’s gonna sound different depending on where you’re standing and what room you’re in, and how many speakers are in your cab, but nobody mics up guitar cabinets the way you’re describing, unless they’re trying to add ambience to the close mic. And certainly nobody mics up all 8 of the speakers in a 8x10, or all 4 in a 4x12. That would serve no real point in a functional recording. So yea, he’s doing it the only sensible way to do it.
Glenn Fricker over at SpectreSoundStudios (YT) does a lot of A/B tests. I believe he came to the "it's the speakers and the mic" conclusions before Jim here, though I know he's watched Jim's videos too. Glenn certainly has NOT gone as far Jim in building and testing to isolate contributors to tone. Jim certainly has a great scientific method approach to understanding things for "just a performer" or whatever he keeps calling himself.
Me too, just finished it this weekend. Used 100 year old desk for the pine as dry old cabs sound better than new ones. I’ve a/b’d them with same head, same narrow panel 5e3 size, baffle size, speaker.
@@TheBoomtown4 oh no, i hope you didnt screw them together, since old wood loses all its bamf and airieness when they touch post 2000 screws since the metal companies changed their recipe.
I typed "how a guitar cabinet affects tone into the search" and thought I was in for a wild goose chase but this was the first video that came up and it was perfect.
Electrical Engineer here: The impedance *can* effect the sound as it *might* change the way your amp interacts with the speakers, but that depends on the amp. So it might be that in your case the amp could handle all impedances well, while other amps might handle them differently. Impedance mismatches can certainly also effect the frequency graph (e.g. try running a High-Z Piezo into an low-Z preamp vs running the same thing into a High-Z-Preamp). But with amps it really depends how the output section is built, e.g. a change in impedance might form a different "passive filter" with any internal capacitance of the amp, etc. However I don't think impedance is a big factor in the sound of an cab typically. It might affect the effectiveness (how much levels you get out of the whole thing), but not so much the sound as long as your amp-cab combination is within spec : ) Some additional thoughts: You looked exclusively into the frequency domain which was a really interesting (and worthwile) exercise. But be aware that the time domain also exists (REW can do waterfall plots). Some of the changes you made might not have shown big changes in the frequency graph, but might have affected how the cab handels short impulses, percusive sounds and such things in the time domain, which in turn might affect things like the perceived "tightness" of a sound. I believe the biggest changing factor there would still be the speaker itself, unless you are building some boomy bass-reflex thing replacing the hole in the back with a pipe or something. But if you have the speakers around still, looking at how they "ring out" when fed with short pulses might be an interesting thing to look at as well. Your work is really gold, thanks.
A change in impedance comes also with an important change on the amp's side - if a) you don't mismatch and b) you use a tube amp. What I'm talking about is the difference in the output transformer's secondary windings. This is what you change when dialing the amplifier's impedance switch. So there really is no (simple) telling what role the amp or the speakers play when comparing impedances.
It’s interesting that I have seen some speaker manufacturers show different response plots for the same speaker that is available in different impedances. It’s not much difference, but it’s not zero either.
Jim probably has no appetite for revisiting given how much data was collected on this video, but repeating with time domain recorded in waterfall plots would be pretty definitive, and actually pretty groundbreaking! I'd even happily contribute to a crowdfund for your time doing that
in a speaker, the only thing impedance effects is the load on the amplifier. otherwise the ohms dont matter. they have absolutely no effect on frequency graphs, and "mis matching" impedance is also another marketing ploy that has no actual effect on anything other than the load present on an amplifier. especially considering the fact that a speakers measurable impedance is a meaningless value that changes as soon as the speaker is in use. but in an amp, changing impedance will NEVER effect your sound in ANY way, aside from decreasing its total output power.
I have never sent a PayPal to a content maker…until now. This was absolutely incredible and so well done. I cannot believe how much work you put into this and how valuable this debunking of mojo voodoo secret sauce actually is. More please!
@@crazyjack9voltbatteryamps I hear you and that’s a fair point. I certainly have gone through many speakers and cabs during my career. Some sound “better” to my ears and feels better to play when matched with the right amp, guitar, and style of music. I think what this video demonstrated more than anything, and the reason I made my comment, is that a $500 speaker in a $1000 cab most likely is not dramatically better than a much cheaper setup. Cabinet constructionv, meaning solid joints, is definitely important to speaker efficiency. However, for most studio work and certainly live there’s a lot of close miking going on so I’d say this video is informative for that context.
"... so I did the work..." I love that this is repeated so often. I wish more folks making videos like this would reference this thought more. Not everything requires us to duplicate so much work of anyone before us in order to learn, but if we really do want to do well at anything, at some point(s) there will be lengthy, arduous work we'll have to do to reach our goals and beyond. TH-cam is an amazing resource, Jim is gift, and after watching his work, we still have plenty to do.
At one point (17:13 to be exact) you say "I'm just a musician, I don't know anything about physics...". I beg to differ. Here's a quote from wikipedia: "Experimental physics is a branch of physics that is concerned with data acquisition, data-acquisition methods, and the detailed conceptualization (beyond simple thought experiments) and realization of laboratory experiments. It is often contrasted with theoretical physics, which is more concerned with predicting and explaining the physical behaviour of nature than the acquisition of empirical data." By that definition, I would say that you are an experimental physicist, and a good one at that. Love your videos, carry on.
This sure is part of the job of a experimental physicist. But he should get the data, calculate the correlations, X², z index, p value, describe the wave change based on the free parameters etc. But he sure did a good job
I think he's jesting. He knows damn well he's going beyond what 99% of the performing musicians is doing or even capable of thinking. It's also a very subtle way to ask the guitar press why he should be doing their job.
Your conclusion is correct. The air inside the cab acts like a spring and a dampener on the speaker cone. Depending on the volume of the cabinet, this can dampen or boost certain frequencies. Furthermore, the geometry of the cab creates standing waves inside it, which oscillate at specific frequencies, acting in or out of phase with the speaker, boosting or dampening certain frequencies. It's a pretty complex topic that I haven't look at in well over 10 years. Guitar cabs are pretty simple, but you wait until you get into Hi-Fi subwoofer design, with tuned tubes, tuned enclosures, and passive speakers. Also, Eminence Audio still have a cabinet design simulator.
@@kenigma4303 Similar, yes. The main difference is that the "cabinet" for an acoustic guitar is also the "speaker cone". But yes, the volume of air creates a certain spring/dampener combination which tunes the frequency response of the body. The standing waves inside be cavity in conjunction with the sound hole also determine tone. In theory, if you move the sound hole of an acoustic around the front face, you should get different tones.
@@CristiNeagu I guess I was just thinking of the waves of sound moving around inside the cabinet or acoustic guitar body similar to how the waves of light are reflected inside a properly cut diamond. The better the cut, the more shine comes out of the same initial gemstone. That’s why I was wondering if there is an objectively ideal shape (or shapes) to an acoustic guitar and subsequently, a speaker cabinet. Listening to the video, to me the large cabinet had the most full and deeply resonating tone.
@@kenigma4303 Depends what you mean by "ideal". Some people like more bottom end, some don't. Also, it's always a compromise, so you can't get everything perfect.
You legend. You just demolished about a million different tone myths in less than 20 minutes. I couldn't tell much difference between polystyrene cab and orange cab tbh at the end! Amazing.
Great practical testing! Your conclusion at the end is spot-on and is related to a phenomenon called acoustic impedance - this is similar to electronic impedance in that the speaker cabinet acts like a transformer to match the impedance of the speaker to the impedance of the air, which combined with phase shift and diffraction effects results in the response you see from different speaker cabinets. What's really fascinating about this is you can measure a change in electrical impedance of the speaker coil when you change the acoustic impedance by mounting it in a cabinet. It's pretty well-understood what affects the response of a speaker cabinet, so I see this topic as more of an education issue. Speakers are relatively easy to model mathematically and you can get about 90% accurate from design equations that use the parameters of the driver and the speaker cabinet. This is easy using a graphical program like Hornresp or Akabak. The mystery of speaker design/sound is mostly limited to guitar cabs at this point due to tradition and superstition running deep in the industry, which stands in stark contrast to the scientific approach used in modern PA equipment. But like you observed, as long as your speaker cabinet walls are suitably stiff, only the volume of air and dimensions of the baffle and any ports matters (besides which speaker driver you've selected). A huge issue with guitar speakers is they don't typically publish all of the driver parameters, so the only way to accurately design a cab is to measure the driver yourself in most cases. Measuring the driver parameters is pretty easy with some cheap test equipment. Also worth measuring is polar response (as you rotate around the speaker), as baffle diffraction and such have a huge effect on how the speaker sounds around the room, especially for cabs with multiple speakers. If you'd like to to a follow-up video doing some more in-depth tests to explore the science/process behind speaker design I'd be happy to help! With regard to your 5:20 tests, the transition from closed-back to ported and into open-back depends on the cabinet volume and the driver parameters. At a conceptual level, your test represents the following conditions: 1) With no holes, the system comprises the speaker driver (with its mass and springiness) with a spring formed by the air in the cabinet attached to the rear of the speaker cone (sealed/closed back). This is a second-order system that provides 12dB/octave of rolloff in the bass. The main issue with designing a speaker cabinet concerns what to do with the wave that comes off the back of the speaker cone, which is 180 degrees out of phase with the front wave and will cause destructive interference. A sealed cabinet resolves this by simply trapping the rear wave, preventing it from canceling with the front wave. This results in a boosted bass response compared to a speaker with no cabinet, and the spring of air inside the sealed cab provides protection for the speaker driver by resisting large excursions. 2) With a few holes, another mass on a spring (a port) is attached to the sealed system. The air in the holes you drilled act as a single mass that bounces against the spring of air inside the box. This is exactly the same effect that makes a bottle whistle when you blow across the opening or causes an acoustic guitar to emit bass from its soundhole, Helmholtz resonance. As you probably know, you typically add a port to boost bass response on a speaker. I think in your case the speaker driver just has an unsuitable motor for actually driving a port, so you mostly just saw the decline in low bass response associated with ports, but if you look at the red plot at 5:56 there's a boost in the bass response where the port tuning is as good as it's going to get for this driver. If you mounted a speaker with a more powerful motor (higher magnetic field strength) and stiffer cone, then it would produce a lot more bass, likely at the expense of mid and high response. A fun modification to an acoustic guitar is to actually tape a tube into its soundhole, extending the bass response but decreasing the volume. The tuning frequency is proportional to the area of the port and inversely proportional to the depth of the port. An intuitive way to think about this is a longer port hole provides more travel distance for the air in the port, lowering the tuning frequency because a longer wave is needed to push and pull the air in and out of the port. Don't let the velocity of the air in the port confuse you either - the sound waves always travel at 343m/s, so the velocity of the air in the port is only related to the amplitude of the sound. A larger diameter port hole allows more air to move, but also must be proportionally longer to provide the same tuning frequency, so ports are made as small as possible without having excessive turbulence. If a port is too long it also causes secondary resonances that sound bad in the midrange. With a port attached, the speaker behaves almost the same at high and mid frequencies as in a sealed system, but as the frequency approaches the resonance of the port the speaker driver itself actually stops moving, instead transferring all of its energy to the mass of air in the port and setting that into motion. This is the acoustic impedance phenomenon you hinted at in your conclusion - the ported enclosure presents a favorable impedance that allows the driver to do more work at the port tuning since the enclosure is allowing the speaker to push harder than it would be able to otherwise. The result is increased bass response at the tuning frequency of the port (mostly limited by port turbulence and thermal capacity of the speaker driver), but now there's a hole in the box, so below the tuning frequency of the port the bass disappears twice as fast as in a sealed system (24dB/octave, a fourth-order system). The speaker also receives no protection from overexcursion at low frequency, so a high-pass filter is usually required. 3) With the larger full-width cutouts, the box is effectively open, eliminating the extra springs in the system so the speaker is basically equivalent to being mounted on a flat baffle. Any resonance is from the speaker's own mass and suspension. This is called open baffle loading and results in a dipole speaker. Bass response is poor due to destructive interference of the front and back waves, with the mid response determined by baffle dimensions and the resulting diffraction. Frequency response changes dramatically as you walk around the cab due to diffraction and interference effects. The response pattern is similar to a figure-8 microphone. Siegfried Linkwitz has some fascinating insight and designs on dipole speaker design, which can help inform you when positioning open-back cabs. The same loading condition can also be achieved by mounting a large speaker into the wall of a room, but the bass response is actually good because the rear wave is discarded outside of the room - this configuration is called infinite baffle. Open and infinite baffle are both dangerous to the speaker driver for the same reason as a ported cabinet - nothing prevents the speaker from being driven past its limits at low frequencies besides its own suspension. It's also worth mentioning transmission line cabinets to help understand how a ported cabinet creates more bass. If you imagine a ported cabinet, but make the port the size of the baffle and lengthen it until you get the low frequency you want (so the speaker is a long tube), this is a transmission line. The length of the tube is 1/4 the wavelength of the lowest frequency you want to tune the speaker to. This results in a very messy response (comb filtered), but between the first and third harmonics of the tuning frequency you get a massive increase in amplitude and efficiency compared to almost any other type of speaker. The reason for this again comes back to the speaker cone simultaneously emitting a wave at 0 degrees in front and 180 degrees in back. At the tuning frequency (first harmonic) we know the rear wave is delayed by 1/4 wavelength, or 90 degrees, so the result is the front and rear waves are now only 90 degrees out of phase and will thus partially add instead of cancel. The act of delaying the rear wave creates constructive interference at the tuning frequency, so we're just making better use of the energy that's already there. This is actually what a ported speaker cabinet is doing - introducing phase shift to the rear wave from the speaker driver by time delaying it so it can add to the front wave, but only at a specific frequency band because this time delay would need to grow longer as frequency goes down. The same delay phenomenon is part of why you don't see transmission line designs very often. Unlike a ported cabinet, which behaves like a sealed cabinet above the tuning frequency, in a transmission line the phase rotates 90 degrees for each harmonic. So the second harmonic results in 0 degrees phase difference and max addition, third harmonic is 90 degrees just like the first, but the fourth harmonic is now 180 degrees out of phase and cancels completely, which is very inconvenient because this is typically in the midrange unless you've built a very large subwoofer. In literal terms this means you get a speaker that only has a frequency response from 20Hz-60Hz, 40Hz-120Hz, etc., but it is extremely efficient and loud in that range. The other main reason you don't see these is size - a transmission line tuned to 30Hz is almost 3m long to achieve 1/4 wavelength. Transmission lines are actually the simplest type of horn loudspeaker and provided a good foundation for understanding how those work.
Some great points there! However, a couple of very important points that you’ve overlooked: 1. It’s only (relatively) easy to model a speaker’s behaviour at low frequencies where the T/S parameters can describe its characteristics and when the cone can be treated as an ideal piston. Above 200Hz modelling would require extremely advanced FEA based on very detailed measurements, using the kinds of machines Klippel sell. 2. Low frequency modelling as pioneered by Thiele and Small only works with small signal levels, and “small” is defined by the driver operating wholly linearly. Guitar speakers hardly ever operate linearly due to their minimal (or zero) voice coil overhangs, very light cones and relatively stiff suspension. So low frequency modelling of a guitar driver might seem useful but it may actually give results that don’t reflect the real world usage.
This was the purest form of the scientific method and a huge eye opener. I have mesa and orange cabs that all have V 30s but sound so different. Cool videos.
As an engineer, I love this no-hype systematic approach. Do yourself and everyone else a favor and make cabinet impulses of all nine of your cabinets and monetize this content even further. I'd buy it.
@@CristiNeagu in all fairness, a bad cable can and will crap on any sound chain and drain any soul from the tone before it even hits the first true bypass organic analogue boutique germanium trve cvlt pedal some may have on their pedalboard. Jacks, not that much, it just needs to make decent contact, no rust/dust. 🙂
As you were going through the 12 factors I was thinking "too bad he didn't make a cab out of something crazy like plastic or concrete". And then you came with the Styrofoam. Phenomenal work, man.
for simply the thoroughness and informativeness of the video, you have my appreciation. for building 9 cabs from scratch just for the research, you have my admiration. for ending the video with a blind comparison between the orange and styrofoam cabs, you have my utmost respect.
Excellent work! I recall some theory to add to the collective knowledge that folks have been posting. 1 - tuned ported boxes are more efficient (louder) because you are combining the energy from the back side of the speaker cone in-phase with the energy coming from the front, albeit prone to boominess (time domain as mentioned) in the low end and the cone has less resistance and will travel further; 2 - a properly sized *closed* box will produce better, tighter lo-freq response in a smaller box, but will be less efficient because you aren't using energy off the back and because the internal air pressure acts as a damper, 3 - most raw speakers have a spec from the manufacturer recommending the optimum cabinet internal volume in cubic inches or cm for a particular speaker; 4 - hifi boxes contain absorptive materials (on three of the opposing sides) to prevent standing waves which affect the sound as someone has noted here. 5 - speakers designed to be installed in an open back or ported box have a more rigid surround because there is no air pressure damping. A speaker designed for closed box runs the risk of damage if used in an open box. 6 - you stumbled upon opening size making a difference. Each speaker/box combination would have a perfectly calculated tuned port that would cause the energy coming from the back side to join up in-phase with the front. And this mostly affects low-end. You can put a tuned port on the front and experiment with different lengths of tube until you get the thing in tune. 7 - just a guess here, but guitar amps are mostly concerned with midrange, so manufacturers can be less concerned with producing a perfectly tuned box. 8 - I once read that the most efficient material to make a speaker box would be concrete. Vibrating wood is energy loss. That would explain why your sheetrock version sounded like the thick wood of the orange cabs. if you append this experiment, I would be interested to hear a comparison of all the variations vs a cabinet of the man. recommended internal box volume for the speaker, mounting the speaker as intended (closed or open.) update - i couldn't find info on the ideal box size for a celestion 12", so maybe all my theory only applies to hi-fi speakers.
What you've encountered with the hole thing with the low end slowly coming back up is the idea behind bass reflex cabinet designs - stick a specific length of pipe in that hole and you get _way more_ low end from a helmholtz resonator.
Bass guitar cabs are semi reflex designs. Ported designs tend to be a bit boomy at key frequencies, so bass cabs restrict airflow using a vent with a larger open area (see SWR Goliath or Eden David which have a slotted port at the bottom and sometimes top of the cab). This was a big thing. The first bass cabs were adapted guitar designs, but they needed ridiculous amplification. Then came literal horn loaded PA cabs connected to power amps and rack mount preamps in the mid 70s. More efficient (and smaller) cabinets like the Goliath made it physically easier to be a gigging bass player.
Jim "So I Did The Work" Lill...Thank you for doing what the rest of the internet is unwilling to do (myself included) and what companies most likely would not want to share. This is beyond impressive!!
Thank you for doing the work! The Helmoltz frequency is what describes that "complex relationship between bass response and the size of the opening in the back panel". This is a well documented phenomenon where a hole in an otherwise closed volume can lower it's resonant frequency. This is why sub woofers often have ports. It's also why the size of the hole in an acoustic guitar is very important
Thing is with holes and cuts in the back the aspect ratio of the hole is very shallow so effects like the coupling zone really get to play here. So it's a bit more difficult than a simple Helmholtz resonator
as far as ports... yes and no. the volume of air inside of a port actually acts as an independent source of resonance. In a sense it is a smaller speaker made of air. th-cam.com/video/PoEyIJx3uM0/w-d-xo.html
With the hole you are actually building a ported speaker. Air has a mass and by drilling a hole, you are building a "air-speaker". This is used in subwoofers, to build bass reflex / ported subwoofers. This is also why the sound is falling off in the deep end more quickly. Those videos are amazing. Love the aspect of actually playing those back to back and comparing them.
Afaiw you need some kind of tube for a ported speaker. Open backs would be more similar to trabsmission lines or rather open baffles, where the increased distance (through the back and around the cabinet) between backside and frontbaffle make the soundwaves from the front and back dont just destructively interfere but might even add up or anything in between
@@torgeeee You don't need a Tube for a ported speaker. The Port can have every form. But of course it has to be calculated (thiele small for example). Depending on the calculation the opening can actually just be a hole in the cabinet. I build speakers in which it has only been a small slit and ones with a rectangle tube/tunnel like opening. But just by adding an opening you construct a type of "air-speaker", if its fitting for the speaker is of course a different story. I don't think you can compare the open baffle on the back with a transmission line. The transmission line works more like a flute and is a monster to calculate. This is where you would really need a tube like construction. More so in the Transmission line then in a ported "subwoofer" or speaker system..
I think this is by far my favorite video in this series. Besides musical instruments, my other hobby is hifi speakers. The construction of the speakers determines what kind and size cabinet it should be on, plus sealed vs ported affect on bass response. Your closing statement hit the nail on the head.
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Not too scientific after all! 🙂
Every time you say "So I did the work" it put a smile on my face. You are one of my new favorite channels because of this. Not wasting everyones time talking or theorizing about what might be causing things, or regurgitating what others online say about what causes things. You just put the work in to track down the results, no matter how time consuming or tedious it may be. I hope you can find plenty of new topics to perform these sorts of tests on for guitar and music as a whole because it's super interesting having all of the myth broken down
The fact that you didn't reveal which was which at the end speaks for itself. You didn't need to because it doesn't matter, they sound so similar that the difference is completely negligible if there even is one. Great work!
Man when you make a video you go HARD... Fun to see all of this compared. Personally, I play a Marshall plexi through a rather unusual 4x8 cab with celestions, this video again confirmed that I really need to upgrade to a 4x12. As for the slanted vs straight cab thing, as you said it doesn't matter when you're miking it up close, but it very much matters in a live situation. Because 2 of the 4 speakers are slanted upwards in slanted cabs, they have a much bigger sound dispersion, allowing you to hear yourself better if you're standing within 3 feet of your amp (say, on a small stage), and allowing your band to hear you well too. If you're in the same position on stage playing a straight cab, because of the somewhat limited sound dispersion and your head being above this area, you cant hear yourself well, so you turn up your amp. All the while, your band members standing further away can hear you just fine, so by turning it up you're just pissing them off (ask me how I know).
Agree! As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Just saying! 🙂
So back in uni, I got this good deal on a H&K Tonemeister head. I didn't have enough money to buy a cab with it, but I saw someone selling a V30 for a good price and convinced myself it was a good idea. Made the shoddiest cab, with a removable back slot, and it didn't sound bad at all. I remember when building it, people told me that it won't sound good, but watching this has brought me some personal affirmation
“So I did the work”. Heck yeah you did. This was epic. There’s another guy on here, Johan Segeborn, that has a ton of videos comparing the sounds of speakers. Mostly Marshall cabs and greenbacks. But even amongst them there are significant differences in tone. It’s amazing how little attention is paid to speakers and cabinets. When they’re really the key to tone imo. No doubt everything in the chain has an affect. But speakers and cabs are way overlooked for how much they do to the sound.
Johan did some interesting experiments comparing grill cloth material, cabs and wood used for guitar construcion, too. His channel is definitely worth checking out!
As just one example, the Boss Katana Artist boasts improved modeling this and amplifying that, but if you put the output of a Katana Artist into a Katana 50 it sounds just like the 50, while if you put the output of the 50 into the Artist it sounds just like the Artist. The difference is all in the speaker and cabinet. And, as we learned here, that's all in the speaker and cabinet geometry.
I've been using these videos to teach my kids about science and analytics. Absolutely perfect. I've had plenty of researchers and analysts who are paid well into the six-figure range, who really need to take a few lessons from Jim Lill. Such good work. It's a joy to watch his process.
this is the greatest guitar tone video ive ever seen in my entire life. massive props on the empirical standardized testing with REW and the sheer man hours of building all those cabs!
I can only imagine the amount of work that went into this! While other people criticize your results, you're the one actually testing, and putting in the work while they just philosophize on how you must be wrong. Keep on doing what you're doing. It's very much appreciated.
Great work Jim! Of course, it's only a matter of time until they start making cabs out of "toan foam"...and there will be a line of suckers to buy it. As you said, it's just physics. Anything that shapes the sound waves and their path to the mic, shapes the sound you hear in the end. You can get more noticeable tonal change by simply moving the mic around on any given cab than by owning 12 different cabs. Sadly, that doesn't sell cabs, so it is ignored in favor of various and sundry gimmicks. Thanks for keeping them honest. Cheers!
Well... He didn't test putting sound absorption inside the cab (known quantity where you can look up frequency response for different materials). He could have also tested his idea by using different materials on the back of the cabs. The other big one from the audiophile world is cabinet bracing (hinted at with separate sections within the cab) and even wildly different sized speakers and ports. It would be interesting to have him pull what he thought was the best sounding cab and try to build something similar sounding at a lower cost (JL cabs coming soon).
@@quintessenceSL I think it would be more interesting to get people who think that these things make a difference in a room and do a blind study to remove placebo as a possible source of perceived sound difference
I don't think tone foam would go over too well simply because gear is already easy enough to damage. But this does prove there's nothing wrong with fiberboard for cabinets, except some of the really cheap stuff that smells funny and is probably bad for your health. Many exceptionally well regarded speakers use MDF cabinets with a wood veneer, because the working properties are much more similar on all axes and much more consistent from one piece to the next than with natural cuts of wood.
The low-frequency drop-off below 200hz is from "phase cancellation". The front of the speaker driver's cone directly radiates sound waves, as we all know. What may not be known is the back side of the driver directly radiates sound waves, but 180 degrees out of phase with the front wave, cancelling out low-frequencies. Awesome, unbiased real-world scientific testing that settled alot of arguments. Great job!
bro I just want to leave my thank you here. You have spend a whole lot of time in order to experiment with every single possible config in every single possible aspect of tone in order to spare us the effort. Thanks a lot.
Obviously, lots of work went in to this - not just in building and filming but in all the thinking and managerial work of editing it into a cohesively formatted presentation. Kudos on all of that and the bits that can't even be put into words. As a sound engineer, both studio and live, for 27 years now and a woodworker for even longer I will say a few things that will likely make you want to kill me. First thing. It's not just the cab, it's the room. Take any cab into 3 differently sized spaces and, using the same amount of power at the same ''volume'', you will get different EQ responses. The diaphragm of any mic can only behave relative to its environment, like a goldfish grows smaller in a smaller bowl but place it into a larger bowl and it will grow larger, it's directly proportionate. Increasing the power to a given cab in a larger space. that initially sounds thin in that space but beefy in a smaller space, does several things that resemble torque curves seen from combustion engines but to the sustain of whatever resonances that cabinet otherwise has. The changes have to do with how voice coils are built and the mass/size of the driver relative to the power and air resistance in the room. The cabinet's construction will either perform great in a 7x11 bathroom or a 16x 24 bedroom or a 3x4 closet, but likely only one of them, and if it does will likely then be trash on a stage. I have my beliefs, I'm sure you will have yours, but there DO exist specific parameters at play as to how to use these phenomena either for or against your patience levels and/or sanity breakdown threshold. Second thing. Pine or spruce face plates, full-stop. The mid range frequencies at play in electric guitar are very similar to the low mids of a violin. To dissipate them so that none of them ''stand'' you need to avoid both thin/flimsy and dense/rigid faces. The point being you want to reduce cabinet resonance, which do feed back through the face plate, but not leave it dead. I've tried at least 10 different face materials and pine has been the best overall. Double it up to 1.5'' and leave the mounting ring the speaker fits into at .75''. Think about what is going on when a snare drum shell is mic'd (ie from the side). That shell is definitely audible and it sounds totally different than either the batter side or snare side, same as the back and side materials of an acoustic guitar make a difference. The pine/spruce face just sends sounds wave through it FAST and consistently - without adding noticeable ooompf to bass notes. Third thing. Close micing ain't always it. I've gotten great results at 5' on cabs that just sounded trash within 2-6'' in any space. If the mic is always within 2'' and the volume is always above 95db then don't even bother unless you're just doing a solo performance as any other band instruments will negate 99% of any nuance the cab COULD ever offer. Once you get out around 1.5' the cabinet material begins to matter A LOT.
Dude, you're a lunatic😄 I can't believe how much work you've put into all of these videos. Truly a priceless service you've provided, and an amazing groundwork to build off. I hope that the message gets through to enough people that they don't need to keep jumping through so many hoops and spending so many thousands of dollars on things that don't affect the sound they're after. It's great to be able to focus on what really matters.
Yeah, because no one has done this before... EVER. This is the first time... EVER. Now he can invent speaker cabinets for the first time for everyone. You know, if this guy never came along and figured all this out, we would be living in the dark ages still.
@@scottyharris8873 No need to be mean. Of course speaker manufacturers do these tests all day, but they do it behind closed doors. Making this info public is God's work.
@@scottyharris8873 get a grip, dude. How many consumers actually understand what affects the tone in a speaker cab? How much marketing nonsense and baseless myths do most people get bombarded with when trying to buy one? Don't be a tool.
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Just saying! 🙂
Not gonna lie, I only heard differences for like four of those 12 changes, but that styrofoam cab at the end was an awesome demonstration of the take-home message. Well done sir.
@@electrifried Exactly. That's the importance of blind tests. When we already know what we are listening to, we tend to hear what we think the differences might be or what we think should be "better" even if there is no difference. With a blind test our preexisting biases don't get in the way.
I think what you are doing in these videos is just fantastic. You are basically approaching tone with no preconception at all, like a science researcher would do. Awesome.
Jim must be the hardest working man in showbiz. Not necessarily on stage... but certainly in the wood shop. Give this guy a hand to get him the subscriber and view counts he deserves.
60's Fender 2x12 cabinets had insulation installed to absorb some of the frequencies bouncing around inside the cab. This insulation is often used in hi-fi speakers to improve frequency response... would love to see you go down that rabbit hole!
Interesting theory about why the Open vs Closed back cabs sound different. The speaker moves back and forth to create sound inside the cab. In a closed cab, despite not being air tight, the movement of the speaker causes variations of pressure in the air inside, that is, if the speaker moves backwards it encounters a resistance due to positive pressure, and if it moves forward it does encounter a resistance due to negative pressure. On the contrary, on an open back cab, the air inside the cab flows way more easily in and out, therefore applying little to no pressure in the speaker cone when it moves, and thus allowing it to vibrate more freely, and in general to move "more" back and forth. This phenomenon is more noticeable in the low end, which are the lower frequencies which require a wider movement by the speaker cone. This theory would explain why the size of the hole in the back also affects the tone, in that it affects the air flow in and out of the cab.
This reminds me of an interview with Mark Bartel who was saying he thinks of his speaker cabs as acoustic instruments and is very focused on the way standing waves inside a cab can build up. Volumetrically, understanding the air movement inside the cab and allowing for it to get out in the right ways seems like fair pursuit.
I'm curious how much these differences apply once you start backing the mic off of the speaker and get more of the room in the mic signal. I'd think the speaker amount and straight vs slant would have a much bigger effect as you start pulling the mic out. The styrofoam cab was pretty fucking mind-blowing though holy shit. Really gives you something to think about for live situations that are usually only close mic'd anyway, might as well just build a cab that is the best combination of lightweight/portable and sturdy to make touring and setup much easier. Great video! This definitely took a lot of time and dedication and it shows!
"The styrofoam cab was pretty fucking mind-blowing though holy shit. Really gives you something to think about for live situations that are usually only close mic'd anyway, might as well just build a cab that is the best combination of lightweight/portable and sturdy to make touring and setup much easier." The rub here is that wood is actually a great choice of material if you're trying to balance durability, workability, affordability and weight. There aren't too many other choices that make sense. Molded plastics are one option that works well, which is why you see so many plastic PA speakers and studio monitor enclosures these days, but wood is still favored by smaller builders as they can cut and shape it any way they like without having to involve an outside plastics manufacturer.
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Just saying! 🙂
I’m currently building a 212 cab, and I’m using this video as reference. Thank you. I’m also an engineer, and your “Design Of Experiments” (DOE) method is almost exactly like what I have done. DOE is GREAT at finding interactions, relationships, and thing that have little effect. Nicely done.
well - not only did you do a LOT of work, you also had a method to what you were doing and are good at explaining what you did and point out the results you felt/got. Excellent job!
These videos just keep getting better and better. The amount of work that goes into the experiments is one thing, but tracking every result, organizing it, and presenting it via brilliantly executed audio/video cuts is extremely time consuming and labour intensive. I'm excited about where this channel will take us as you move on from guitar to Pro Audio in general. I think it's important to mention that your content is not only highly entertaining, it truly is a public service. Thank you!
This video is exactly why I like TH-cam and all the amazing people who make such awesome videos for everyone to enjoy and learn! Huge thanks, man, it’s really cool!
The strips of wood on old amps are diffusers and disperse the treble frequencies wider in the room. The treble frequencies gradually disappear the further you move off-axis from the speaker cone.
One huge thing that wasn't tested is the sound in the room as opposed to right in front of the speaker. For recording, a 57 right in front of the speaker is absolutely valid. But the vast majority of the sound when you have a cab in the room comes from the sound being dispersed at an angle. The strips of wood might make it sound a bit too dull in comparison, but they actually remove the "icepick" effect that is caused right in front of the speaker, basically making the speaker have a more balanced response at a wider angle, and therefore a smoother tone for more people in the room.
@@distortingjack I agree that he should have recorded the room at certain angles. My band played a gig a few years ago and people on the sides of the room were complaining that they couldn't hear the guitars. It sounded fine to me, but I didn't realize that the treble frequencies disappeared tremendously for the folks sitting on an angle. I did some research on dispersion and diffusion (duct tape, beam blockers, Mitchell Foam Donut). On my 1x12" combo, I taped a 6 inch piece of very thin foam (3mm) in the center, with a 3/4 inch hole in the center. The small hole in the middle acts like a tweeter and spreads the high frequencies very evenly...no more treble beam of death coming from my amp!
Wow, we appreciated your high commitment. We all know we're buying cabs for the brand.. well, they sound about 90% the same to be honest depending on the ports & speakers.
"What if we don't hear the cabs resonate" at 17:24 was a home run for me. I make flutes out of materials like PVC pipes, and people are often surprised that they sound really good. The reason they sound good is the same as in speaker cabs - the material doesn't resonate audibly, only the chamber of air inside does. In a flute it's the smoothness and straightness of the body, the geometry of the finger holes, the shape of the mouthpiece etc., that shape the tone. (Which makes PVC great because it's manufactured with consistent geometry. I don't have to be nearly as skilled as if I was making them from bamboo). The one caveat is a material's dimensional stability does matter; an instrument that changes less in response to temperature and humidity will be easier to play in tune and maintain its tone better. I imagine that in a speaker cab, the dimensional stability of the material could affect the geometry and therefore maybe the sound as well.
@@crazyjack9voltbatteryamps Clearly, if you've heard live Bass at stage volume, you'll hear cab resonance and speaker compression. The effect is much greater with Bass.
This is golden. You deliver every time Jim ! And it just confirms my years of studio experiments : the "magical" cabs are the ones that have the right mix of speakers vs geometry. How they're made and what of is a practical and aesthetic consideration but tone-wise : no significant change.
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Just saying! 🙂
Ideas: -backwave reflections from the inside will cancel and reinforce different frequencies depending on distance from the speaker. Try changing the depth of the back panel so the cab get shallower and shallower. -also try adding damping materials to absorb reflections on the inside. One surface at a time, then pairs, then all. Absorbing direct reflections will make things different! -loose polyester fluff from a pillow left in the cab will absorb low end resonance by converting the vibrations into heat, and it slows down the waves enough so the cab behaves like it's bigger (but with less bass). A boomy cab can be tamed this way. -try to angle the back panel or baffle more and more and see how the gradually less direct backwave affects the frequency response. -surface mounted vs inside mounted speakers supposedly changes things a lot. Interesting?
Dude! I always LITERALLY laugh out loud when you build or do something crazy that is supposed to affect the guitar tone and then doesn't! F*&king Awesome man, really, thank you for doing this so we as players don't get caught up in hype and marketing.
I definitely recommend watching the channel Tech Ingredients, if you want to learn more about the physics of speaker design. They do a fantastic job of practical demonstrations of the science and engineering behind many things. From constructing their own drone, to making their own thermal paste.
My buddies in high school all had subs in their cars and one thing I noticed was a massive difference there is between a poorly home made sub box (cab) and a legit one.
At the most basic level the reflected waves matter the same as pushing someone on a swing. The wave reflecting off the back of the box wants to hit the subwoofer as it’s going back out and ride pushing it out not when it’s coming in and clashing with it. It gets more complex than that but it’s a good starting parallel.
You can cheat a little if you pack them with old clothes. All different sizes of speakers will have a perfect size cab for volumetric efficiency and it will depend on whether they’re sealed or ported as to what that number is and how big or small the box should be.
@@lathiat That's not what's happening with subwoofers, the frequencies they're dealing with have much much longer wavelengths - subwoofer behaviour can be modelled using Thiele-Small parameters. However that rear wall reflection can have a significant effect on midrange response and is one of the differences you hear between typical closed and open-backed guitar cabs.
Thank for for doing the work. All that work! (Now I'm torn. Do I wish well for Jim by hoping his music career takes off, so that he has no time for videos, or that his TH-cam career takes off, so we keep getting fantastic videos from someone that actually tries stuff rather than just talks about it, even if that leaves him no time for making music?)
Amazing work! Thank you. I think using a second mic somewhere away from the speaker to get more of the cabinet sound would be helpful. By only analyzing the sound from a mic placed closely to the front of the speaker, it eliminates the ambient sound from the cab in the room. Having a second mic that is placed to pick up room sound from the cab would be informative. Of course, you would need to control for variables in the room, eg, placement of cab, mic, same room/space with no changes in other items in space, etc. An isolated and controlled space.
Love your videos and love your premise for each one. I'd love to see in a future episode what affects pickup tone. Why do they sound different? The magnets? The ammount of winding?
Would the difference in tone be more apparent with some mics set further back ? Anyway really cool seeing you go through the cabinets so objectively and edited to make abrupt A/B comparisons. I know how a certain responsiveness and tone can inspire one to play more. You really dug in and tried exploring so many aspects- really great thing to share. I appreciate your empirical almost scientific approach, only changing one variable at at time etc.... And nicely produced to boot. I am impressed.
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What I love about this dude is he's a proper scientist but doesnt seem to realise it. He starts out by admitting his limitations and the limitations of his testing. Then he identifies, isolates, and carefully controls his variables one at a time. He enters the testing phase with a total open mind and considers everything regardless as to what his intuition might tell him. He carefully records his methods so others can try to replicate his results. He delivers his conclusions impassively by looking at the real outcome with no regard for any prior bias. Then he opens up his tests to a wider audience to invite their comments and review. Dude knows the scientific method inside out
I'm pretty sure he knows, which makes his videos even better!
He's also an engineer, self-taught maybe, but everything he's doing here is a form of engineering.
Yeah except all the information is not clear because it doesn't say when this versus that, it only shows they are different and you cannot duplicate the results because it is not said nor clearly defined what difference is in progress on the one that is playing, only says what way they are different about the test then your left with , " . . . well oh shit now damn, i am must create all the tests for myself to achieve mine results this was all a teasing non pleasing non useful waste because it only showed me what i am already knew".
@@zAvAvAz You seems confused AF to understand the point of the video.
@@daniloberserk No because in the video it says this: " . . .now try to figure out witch one is witch".
This guy is the guitar snob killer. What a legend.
Yours is the best definition I've ever found about Jim.
Funny thing is, in this video he's just confirming things that amp snobs have been saying all along, things like cab size matters, nitpicky things like that divider
@@jantje155 yeah and to me what follows from that is, if you like the sound of a particular cab from a particular company/place/time/country, the replicas or knockoffs might not be able to copy the sound perfectly. The interaction of the sound waves follows from the geometry in complex ways, and maybe the companies are only approximating the geometry and the small differences change the behaviour of the sound. But then again, maybe things average out in a way where small changes really don't have audible effects. Who knows!
My bedroom has a specific resonant frequency that rings out when I hit a certain note on my guitar. It's possible that if a carpenter tried to create a replica of my bedroom, the resonance might be a bit different.
yup haha, thats because when you talk about electric guitars and tone wood, and all thats stuff doesnt matter, in question of the cabs, it affects more like acoustic guitars, more on how are they made not on what are they made of
@@jantje155 Not really. Amp snobs would list 100 things that they think are more important than cab size.
In 20 minutes you've undone decades of marketing by guitar cab manufacturers to justify crazy prices for a wooden box. Hats off to you!
IF every person who is going to buy a speaker - 1/ watchens this video 2/ agrees with his conclusions...
THat' s 2 big ifs
@@xl000 I mean... Hyperbole is a thing.
You obviously just want to have an argument about how you don't agree with his conclusions. Which is a discussion I couldn't care less about... Even if I tried really really hard.
@@xl000 The conclusions this video comes to are "these are the things that appear to empirically affect the sound a speaker box produces", the only way to disagree with this is to argue that all the testing and documentation was faulty and that none of his tests demonstrates any actual change in the output sound.
This guy is blowing my mind and really making me want to either build or upgrade my old stuff.
@@RockWonder210 fuck yeah make your own sound then have others looking to copy your shit. but build a box in a box so the fuckers don't know wahts up lol
Eventually you will have to play the tackle box through the foam cab using the no-body/no-neck Tele. I love the experiments you do!
The 2x4 might be a better experience since youn can press the strings.
How about the wood glue strat?
Absolutely!! That's the one that I would buy. Rock n Roll is about getting down and dirty!!!
god's rig
@@Komatik_ yes !! The 2x4 guitar would definitely be the cherry on top. 🍒
The styrofoam cab has no business sounding that close to the Orange cab. This is hilarious. Cab makers have to be ripping their hair out at this.
Excellent work. You conducted experiments exactly as one should, and were not afraid to say "this didn't affect the outcome as I hypothesized, so I moved on". Truly the mark of a mature experimenter. Well done.
@@crazyjack9voltbatteryamps How a speaker sounds in the room is far less important than how it sounds recorded. No one records room mics for records, no one hears the cab at live concerts, unless they are in a dive bar - it's all PA. This comparison does exactly what it's intended to do, if you feel it doesn't, make your own. Everyone can make their own decisions based on the information provided
@@remingtonlowe3992That's debatable.. If you like the sound you get in the room you'll play more. The sound you get when you're playing affects your choice of what you are creating at the time. Not everything played is going to be recorded either.
I don't think they're really ripping their hair out - most of the cost of cabs is just the speakers, which matches what he's saying. Then you have a bunch of parts and labor which are a much smaller percentage of that and then a fat margin (won't go into the full costing since that's a business class). It's probably like 30-60% depending on the company, with some of that percentage being brand value, but the idea is that the brand value is earned through quality (which is debatable over time and product revisions). Who should be ripping their hair out are audiophile collectors that try to sell or trade "grail" amps as though you can buy a sound (and thus the "skill" of a master lol) like an old violin.
You are a hero of the guitar community. No hyperbole.
First time I’ve heard “No hyperbole” haha! Is that the new “No cap”? Their meanings are kinda similar
The common sense scientific method to isolate variables is a great start, but the amount of work to test them all? Just WOW!
Thank you Jim!
Dork souls
Guitar Hero
The sad thing is though, that a LOT of guitar players will simply ignore all of his videos and cling on to their myths, maybe even double down and start attacking the integrity of these tests 🙄
This guy seriously built like a dozen different cabs in his backyard just for this video. That's dedication. Bravo
A friend was demolishing 10 old electric organs. He wanted the amps inside. I said, wait, I want the speakers. And the reverb spring units. Have you ever built yourself a cheap guitar amp? What is it? An amp, a speaker and some scrap wood. I just got myself some free speakers, not top quality, still I can simply connect them to a small amp. For clean playing, a larger speaker is always okay. If you want distortion, things are a bit different. But hey, such projects are fun. And when you do your research too, chances are, you know what you are doing. And you learn on the go. Ever wondered why bass amps have 4 large speakers? Would that still work with 3 ones? And could a guitar amp get better, using 4 equal speakers?
@@voornaam3191 an old Bass player pal explained that it was all about air push. The larger the cone more flutter yet bassy and less articulate and Claritied. To push the same amount of air and tighten the clarity replace a 15 or 18 with 2 12's or even 4 10's etc. Or combine using a crossover.
This man isn't afraid of work
He, uhh...did the work.
"I'm just a performer..."
*[has pretty solid carpentry skills]*
Jim deserves his own little wing of the Rock n' Roll Hall of Fame for his tireless work in busting myths and answering the important questions.
They don't want him in the R&R Hall of Fame because the one's running it are the same people perpetuating the lies.
This man is a genius. He does not fall for advertisement and "this is known", he experiments and learns himself. These videos will make so many "audiophiles" and audio companies really angry, since they clearly demystify all their mambo-jambo. The consumer on the other hand learns what really is important and where money is wasted or not. Very well done :)
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Not too scientific after all! 🙂
@@crazyjack9voltbatteryampsbut in the vast majority of cases, what we hear from a guitar amp/cabinet is what is recorded through the microphone placed in front of it. When we listen to our favourite songs on TH-cam, Spotify, CD, cassette, vinyl etc, that’s exactly what we are hearing. And when we are in a stadium listening to a band, the cabinet has a mic in front of it and, again, that is what we are hearing. He explains this in his video about amps. Why the “sound in the room” is actually kind of pointless to worry about.
@@crazyjack9voltbatteryamps well said. half of the info here is accurate but well known (eg. open and close back, size, arrangement etc). try to make a guitar from styrofoam and sell it as a boutique axe :) interestingly enough folks pay high dollars on guitars (when they can) and then they are convinced that cabs doesn't really matter... acoustics is a complex matter. or to look at it from a different angle: venues hire expensive acoustic engineers and designers to get the best and appropriate sound out of they rooms. the reason is the same. you can play and enjoy techno in a bunker but probably not other genres where proper sound really matters. no diss to techno venues ... oh wait, they design their rooms and use high quality speakers too to make the experience perfect :)
@@Jamiecb88Yes, but I think most people watching this video are players….. We are trying to get the best tone from where we’re standing on the stage which includes the air space around us. Way different than what the mic is picking up.
The acoustical principle that's causing the effect with making a hole or opening the back is called "helmholtz resonance". There is a caclulation to find the relationship between the boosting or cutting frequency and the size of the opening.
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Not too scientific after all! 🙂
@@crazyjack9voltbatteryampshis focus is on the close mic sound of the amp for the purposes of conventional recording. Obviously it’s gonna sound different depending on where you’re standing and what room you’re in, and how many speakers are in your cab, but nobody mics up guitar cabinets the way you’re describing, unless they’re trying to add ambience to the close mic. And certainly nobody mics up all 8 of the speakers in a 8x10, or all 4 in a 4x12. That would serve no real point in a functional recording.
So yea, he’s doing it the only sensible way to do it.
No one will ever create such a thorough and clear demo of this stuff ever again, this is actually a masterpiece
Do you have a crystal orb telling you the future? You are scary!
I wouldn't be suprised if @TechIngredients released a similar video in the future
Glenn Fricker over at SpectreSoundStudios (YT) does a lot of A/B tests. I believe he came to the "it's the speakers and the mic" conclusions before Jim here, though I know he's watched Jim's videos too. Glenn certainly has NOT gone as far Jim in building and testing to isolate contributors to tone. Jim certainly has a great scientific method approach to understanding things for "just a performer" or whatever he keeps calling himself.
This man is a national treasure and must be protected at all costs.
Haha, the Secret Service would fit best, I guess.
International treasure
I'm pretty sure guitar gear manufacturers have contracts out on him by now
@@Funkybassuk came to say that!
@@xTheZapper or a hitman
Incredible. I spent a whole day building a 1x12 because the thought of spending $650 for a plywood box was ridiculous. Stoked with the results
Me too, just finished it this weekend. Used 100 year old desk for the pine as dry old cabs sound better than new ones. I’ve a/b’d them with same head, same narrow panel 5e3 size, baffle size, speaker.
Hope you used Styrofoam
@@TheBoomtown4 oh no, i hope you didnt screw them together, since old wood loses all its bamf and airieness when they touch post 2000 screws since the metal companies changed their recipe.
@@NMPshadow haha, I used finger joints and even hide glue to help the resonance.
I went the "bee box" route to save time and money and I love it!
I typed "how a guitar cabinet affects tone into the search" and thought I was in for a wild goose chase but this was the first video that came up and it was perfect.
I am totally exhausted and drained just watching the amount of work YOU did for this video.
Electrical Engineer here: The impedance *can* effect the sound as it *might* change the way your amp interacts with the speakers, but that depends on the amp. So it might be that in your case the amp could handle all impedances well, while other amps might handle them differently. Impedance mismatches can certainly also effect the frequency graph (e.g. try running a High-Z Piezo into an low-Z preamp vs running the same thing into a High-Z-Preamp). But with amps it really depends how the output section is built, e.g. a change in impedance might form a different "passive filter" with any internal capacitance of the amp, etc.
However I don't think impedance is a big factor in the sound of an cab typically. It might affect the effectiveness (how much levels you get out of the whole thing), but not so much the sound as long as your amp-cab combination is within spec : )
Some additional thoughts: You looked exclusively into the frequency domain which was a really interesting (and worthwile) exercise. But be aware that the time domain also exists (REW can do waterfall plots). Some of the changes you made might not have shown big changes in the frequency graph, but might have affected how the cab handels short impulses, percusive sounds and such things in the time domain, which in turn might affect things like the perceived "tightness" of a sound. I believe the biggest changing factor there would still be the speaker itself, unless you are building some boomy bass-reflex thing replacing the hole in the back with a pipe or something. But if you have the speakers around still, looking at how they "ring out" when fed with short pulses might be an interesting thing to look at as well.
Your work is really gold, thanks.
A change in impedance comes also with an important change on the amp's side - if a) you don't mismatch and b) you use a tube amp.
What I'm talking about is the difference in the output transformer's secondary windings. This is what you change when dialing the amplifier's impedance switch. So there really is no (simple) telling what role the amp or the speakers play when comparing impedances.
It’s interesting that I have seen some speaker manufacturers show different response plots for the same speaker that is available in different impedances. It’s not much difference, but it’s not zero either.
Jim probably has no appetite for revisiting given how much data was collected on this video, but repeating with time domain recorded in waterfall plots would be pretty definitive, and actually pretty groundbreaking! I'd even happily contribute to a crowdfund for your time doing that
@Steve Knight Amen! I only managed to take a few classes towards that end and 20 some years later I still have occasional episodic fits. Lol.
in a speaker, the only thing impedance effects is the load on the amplifier. otherwise the ohms dont matter. they have absolutely no effect on frequency graphs, and "mis matching" impedance is also another marketing ploy that has no actual effect on anything other than the load present on an amplifier. especially considering the fact that a speakers measurable impedance is a meaningless value that changes as soon as the speaker is in use. but in an amp, changing impedance will NEVER effect your sound in ANY way, aside from decreasing its total output power.
Jim's not only a great guitar tone mythbuster, but he's got awesome video storytelling chops. Super engaging end-to-end.
Good filmaker indeed
a true bard
I have never sent a PayPal to a content maker…until now. This was absolutely incredible and so well done. I cannot believe how much work you put into this and how valuable this debunking of mojo voodoo secret sauce actually is. More please!
DITTO across the board!!
@@crazyjack9voltbatteryamps I hear you and that’s a fair point. I certainly have gone through many speakers and cabs during my career. Some sound “better” to my ears and feels better to play when matched with the right amp, guitar, and style of music. I think what this video demonstrated more than anything, and the reason I made my comment, is that a $500 speaker in a $1000 cab most likely is not dramatically better than a much cheaper setup. Cabinet constructionv, meaning solid joints, is definitely important to speaker efficiency. However, for most studio work and certainly live there’s a lot of close miking going on so I’d say this video is informative for that context.
"... so I did the work..." I love that this is repeated so often. I wish more folks making videos like this would reference this thought more.
Not everything requires us to duplicate so much work of anyone before us in order to learn, but if we really do want to do well at anything, at some point(s) there will be lengthy, arduous work we'll have to do to reach our goals and beyond.
TH-cam is an amazing resource, Jim is gift, and after watching his work, we still have plenty to do.
At one point (17:13 to be exact) you say "I'm just a musician, I don't know anything about physics...". I beg to differ. Here's a quote from wikipedia:
"Experimental physics is a branch of physics that is concerned with data acquisition, data-acquisition methods, and the detailed conceptualization (beyond simple thought experiments) and realization of laboratory experiments. It is often contrasted with theoretical physics, which is more concerned with predicting and explaining the physical behaviour of nature than the acquisition of empirical data."
By that definition, I would say that you are an experimental physicist, and a good one at that.
Love your videos, carry on.
Wikipedia doesn't always get it wrong. Just on important things that impact society.
This sure is part of the job of a experimental physicist. But he should get the data, calculate the correlations, X², z index, p value, describe the wave change based on the free parameters etc. But he sure did a good job
I think he's jesting. He knows damn well he's going beyond what 99% of the performing musicians is doing or even capable of thinking. It's also a very subtle way to ask the guitar press why he should be doing their job.
Your conclusion is correct. The air inside the cab acts like a spring and a dampener on the speaker cone. Depending on the volume of the cabinet, this can dampen or boost certain frequencies. Furthermore, the geometry of the cab creates standing waves inside it, which oscillate at specific frequencies, acting in or out of phase with the speaker, boosting or dampening certain frequencies. It's a pretty complex topic that I haven't look at in well over 10 years. Guitar cabs are pretty simple, but you wait until you get into Hi-Fi subwoofer design, with tuned tubes, tuned enclosures, and passive speakers. Also, Eminence Audio still have a cabinet design simulator.
Thank you for your information
So you are saying it’s similar to the resonance concept of how the interior dimensions of an acoustic guitar can amplify and shape the sound?
@@kenigma4303 Similar, yes. The main difference is that the "cabinet" for an acoustic guitar is also the "speaker cone". But yes, the volume of air creates a certain spring/dampener combination which tunes the frequency response of the body. The standing waves inside be cavity in conjunction with the sound hole also determine tone. In theory, if you move the sound hole of an acoustic around the front face, you should get different tones.
@@CristiNeagu I guess I was just thinking of the waves of sound moving around inside the cabinet or acoustic guitar body similar to how the waves of light are reflected inside a properly cut diamond. The better the cut, the more shine comes out of the same initial gemstone. That’s why I was wondering if there is an objectively ideal shape (or shapes) to an acoustic guitar and subsequently, a speaker cabinet. Listening to the video, to me the large cabinet had the most full and deeply resonating tone.
@@kenigma4303 Depends what you mean by "ideal". Some people like more bottom end, some don't. Also, it's always a compromise, so you can't get everything perfect.
You legend. You just demolished about a million different tone myths in less than 20 minutes. I couldn't tell much difference between polystyrene cab and orange cab tbh at the end! Amazing.
Difference is low-end. You could miss it if watching on a phone
Great practical testing! Your conclusion at the end is spot-on and is related to a phenomenon called acoustic impedance - this is similar to electronic impedance in that the speaker cabinet acts like a transformer to match the impedance of the speaker to the impedance of the air, which combined with phase shift and diffraction effects results in the response you see from different speaker cabinets. What's really fascinating about this is you can measure a change in electrical impedance of the speaker coil when you change the acoustic impedance by mounting it in a cabinet.
It's pretty well-understood what affects the response of a speaker cabinet, so I see this topic as more of an education issue. Speakers are relatively easy to model mathematically and you can get about 90% accurate from design equations that use the parameters of the driver and the speaker cabinet. This is easy using a graphical program like Hornresp or Akabak. The mystery of speaker design/sound is mostly limited to guitar cabs at this point due to tradition and superstition running deep in the industry, which stands in stark contrast to the scientific approach used in modern PA equipment. But like you observed, as long as your speaker cabinet walls are suitably stiff, only the volume of air and dimensions of the baffle and any ports matters (besides which speaker driver you've selected). A huge issue with guitar speakers is they don't typically publish all of the driver parameters, so the only way to accurately design a cab is to measure the driver yourself in most cases. Measuring the driver parameters is pretty easy with some cheap test equipment. Also worth measuring is polar response (as you rotate around the speaker), as baffle diffraction and such have a huge effect on how the speaker sounds around the room, especially for cabs with multiple speakers. If you'd like to to a follow-up video doing some more in-depth tests to explore the science/process behind speaker design I'd be happy to help!
With regard to your 5:20 tests, the transition from closed-back to ported and into open-back depends on the cabinet volume and the driver parameters. At a conceptual level, your test represents the following conditions:
1) With no holes, the system comprises the speaker driver (with its mass and springiness) with a spring formed by the air in the cabinet attached to the rear of the speaker cone (sealed/closed back). This is a second-order system that provides 12dB/octave of rolloff in the bass. The main issue with designing a speaker cabinet concerns what to do with the wave that comes off the back of the speaker cone, which is 180 degrees out of phase with the front wave and will cause destructive interference. A sealed cabinet resolves this by simply trapping the rear wave, preventing it from canceling with the front wave. This results in a boosted bass response compared to a speaker with no cabinet, and the spring of air inside the sealed cab provides protection for the speaker driver by resisting large excursions.
2) With a few holes, another mass on a spring (a port) is attached to the sealed system. The air in the holes you drilled act as a single mass that bounces against the spring of air inside the box. This is exactly the same effect that makes a bottle whistle when you blow across the opening or causes an acoustic guitar to emit bass from its soundhole, Helmholtz resonance. As you probably know, you typically add a port to boost bass response on a speaker. I think in your case the speaker driver just has an unsuitable motor for actually driving a port, so you mostly just saw the decline in low bass response associated with ports, but if you look at the red plot at 5:56 there's a boost in the bass response where the port tuning is as good as it's going to get for this driver. If you mounted a speaker with a more powerful motor (higher magnetic field strength) and stiffer cone, then it would produce a lot more bass, likely at the expense of mid and high response.
A fun modification to an acoustic guitar is to actually tape a tube into its soundhole, extending the bass response but decreasing the volume. The tuning frequency is proportional to the area of the port and inversely proportional to the depth of the port. An intuitive way to think about this is a longer port hole provides more travel distance for the air in the port, lowering the tuning frequency because a longer wave is needed to push and pull the air in and out of the port. Don't let the velocity of the air in the port confuse you either - the sound waves always travel at 343m/s, so the velocity of the air in the port is only related to the amplitude of the sound. A larger diameter port hole allows more air to move, but also must be proportionally longer to provide the same tuning frequency, so ports are made as small as possible without having excessive turbulence. If a port is too long it also causes secondary resonances that sound bad in the midrange.
With a port attached, the speaker behaves almost the same at high and mid frequencies as in a sealed system, but as the frequency approaches the resonance of the port the speaker driver itself actually stops moving, instead transferring all of its energy to the mass of air in the port and setting that into motion. This is the acoustic impedance phenomenon you hinted at in your conclusion - the ported enclosure presents a favorable impedance that allows the driver to do more work at the port tuning since the enclosure is allowing the speaker to push harder than it would be able to otherwise. The result is increased bass response at the tuning frequency of the port (mostly limited by port turbulence and thermal capacity of the speaker driver), but now there's a hole in the box, so below the tuning frequency of the port the bass disappears twice as fast as in a sealed system (24dB/octave, a fourth-order system). The speaker also receives no protection from overexcursion at low frequency, so a high-pass filter is usually required.
3) With the larger full-width cutouts, the box is effectively open, eliminating the extra springs in the system so the speaker is basically equivalent to being mounted on a flat baffle. Any resonance is from the speaker's own mass and suspension. This is called open baffle loading and results in a dipole speaker. Bass response is poor due to destructive interference of the front and back waves, with the mid response determined by baffle dimensions and the resulting diffraction. Frequency response changes dramatically as you walk around the cab due to diffraction and interference effects. The response pattern is similar to a figure-8 microphone. Siegfried Linkwitz has some fascinating insight and designs on dipole speaker design, which can help inform you when positioning open-back cabs. The same loading condition can also be achieved by mounting a large speaker into the wall of a room, but the bass response is actually good because the rear wave is discarded outside of the room - this configuration is called infinite baffle. Open and infinite baffle are both dangerous to the speaker driver for the same reason as a ported cabinet - nothing prevents the speaker from being driven past its limits at low frequencies besides its own suspension.
It's also worth mentioning transmission line cabinets to help understand how a ported cabinet creates more bass. If you imagine a ported cabinet, but make the port the size of the baffle and lengthen it until you get the low frequency you want (so the speaker is a long tube), this is a transmission line. The length of the tube is 1/4 the wavelength of the lowest frequency you want to tune the speaker to. This results in a very messy response (comb filtered), but between the first and third harmonics of the tuning frequency you get a massive increase in amplitude and efficiency compared to almost any other type of speaker. The reason for this again comes back to the speaker cone simultaneously emitting a wave at 0 degrees in front and 180 degrees in back. At the tuning frequency (first harmonic) we know the rear wave is delayed by 1/4 wavelength, or 90 degrees, so the result is the front and rear waves are now only 90 degrees out of phase and will thus partially add instead of cancel. The act of delaying the rear wave creates constructive interference at the tuning frequency, so we're just making better use of the energy that's already there. This is actually what a ported speaker cabinet is doing - introducing phase shift to the rear wave from the speaker driver by time delaying it so it can add to the front wave, but only at a specific frequency band because this time delay would need to grow longer as frequency goes down.
The same delay phenomenon is part of why you don't see transmission line designs very often. Unlike a ported cabinet, which behaves like a sealed cabinet above the tuning frequency, in a transmission line the phase rotates 90 degrees for each harmonic. So the second harmonic results in 0 degrees phase difference and max addition, third harmonic is 90 degrees just like the first, but the fourth harmonic is now 180 degrees out of phase and cancels completely, which is very inconvenient because this is typically in the midrange unless you've built a very large subwoofer. In literal terms this means you get a speaker that only has a frequency response from 20Hz-60Hz, 40Hz-120Hz, etc., but it is extremely efficient and loud in that range. The other main reason you don't see these is size - a transmission line tuned to 30Hz is almost 3m long to achieve 1/4 wavelength. Transmission lines are actually the simplest type of horn loudspeaker and provided a good foundation for understanding how those work.
I started reading the comment and then pressed the read more button to discover a whole article. wow
No one read this whole thing
good writeup
@@AlphaAchilles Many people read the whole thing, as I did. Personally, I find acoustic theory very interesting, Maybe you don't.
Some great points there! However, a couple of very important points that you’ve overlooked:
1. It’s only (relatively) easy to model a speaker’s behaviour at low frequencies where the T/S parameters can describe its characteristics and when the cone can be treated as an ideal piston. Above 200Hz modelling would require extremely advanced FEA based on very detailed measurements, using the kinds of machines Klippel sell.
2. Low frequency modelling as pioneered by Thiele and Small only works with small signal levels, and “small” is defined by the driver operating wholly linearly. Guitar speakers hardly ever operate linearly due to their minimal (or zero) voice coil overhangs, very light cones and relatively stiff suspension. So low frequency modelling of a guitar driver might seem useful but it may actually give results that don’t reflect the real world usage.
35 years of playing and working with these things, and 3 of your videos made me feel like I am beginning again. Subscribed!
This was the purest form of the scientific method and a huge eye opener. I have mesa and orange cabs that all have V 30s but sound so different. Cool videos.
As an engineer, I love this no-hype systematic approach. Do yourself and everyone else a favor and make cabinet impulses of all nine of your cabinets and monetize this content even further. I'd buy it.
Foam Cab IR?? Sure! I'd be delighted to use it!
The whole idea is to go build your own shit and sound like yourself.
What was the atmospheric pressure ? Were they oriented to north or south ? Was it full moon ?
(Your videos are great !)
I'm more concerned about the cable he used... and those jacks weren't even gold tinted.
@@CristiNeagu in all fairness, a bad cable can and will crap on any sound chain and drain any soul from the tone before it even hits the first true bypass organic analogue boutique germanium trve cvlt pedal some may have on their pedalboard. Jacks, not that much, it just needs to make decent contact, no rust/dust. 🙂
@@CristiNeagu Nobody sprayed any unicorn blood on the cable sheathing.
And was Mercury in Retrograde?
You forgot other crucial points such as ambient temperature, humidity, front baffle porting, and presence of fog machine haze!
As you were going through the 12 factors I was thinking "too bad he didn't make a cab out of something crazy like plastic or concrete". And then you came with the Styrofoam. Phenomenal work, man.
Always have to watch to the end on this channel, you never know what hes gonna do.
Concrete has already been done!
@@DMSProduktions I see a concrete guitar on youtube, but not a cab.
@@userPrehistoricman Johan Segeborn did 1 years ago!
@@DMSProduktions Do you remember what it's called? I can't find it
for simply the thoroughness and informativeness of the video, you have my appreciation. for building 9 cabs from scratch just for the research, you have my admiration. for ending the video with a blind comparison between the orange and styrofoam cabs, you have my utmost respect.
Excellent work! I recall some theory to add to the collective knowledge that folks have been posting. 1 - tuned ported boxes are more efficient (louder) because you are combining the energy from the back side of the speaker cone in-phase with the energy coming from the front, albeit prone to boominess (time domain as mentioned) in the low end and the cone has less resistance and will travel further; 2 - a properly sized *closed* box will produce better, tighter lo-freq response in a smaller box, but will be less efficient because you aren't using energy off the back and because the internal air pressure acts as a damper, 3 - most raw speakers have a spec from the manufacturer recommending the optimum cabinet internal volume in cubic inches or cm for a particular speaker; 4 - hifi boxes contain absorptive materials (on three of the opposing sides) to prevent standing waves which affect the sound as someone has noted here. 5 - speakers designed to be installed in an open back or ported box have a more rigid surround because there is no air pressure damping. A speaker designed for closed box runs the risk of damage if used in an open box. 6 - you stumbled upon opening size making a difference. Each speaker/box combination would have a perfectly calculated tuned port that would cause the energy coming from the back side to join up in-phase with the front. And this mostly affects low-end. You can put a tuned port on the front and experiment with different lengths of tube until you get the thing in tune. 7 - just a guess here, but guitar amps are mostly concerned with midrange, so manufacturers can be less concerned with producing a perfectly tuned box. 8 - I once read that the most efficient material to make a speaker box would be concrete. Vibrating wood is energy loss. That would explain why your sheetrock version sounded like the thick wood of the orange cabs.
if you append this experiment, I would be interested to hear a comparison of all the variations vs a cabinet of the man. recommended internal box volume for the speaker, mounting the speaker as intended (closed or open.)
update - i couldn't find info on the ideal box size for a celestion 12", so maybe all my theory only applies to hi-fi speakers.
What you've encountered with the hole thing with the low end slowly coming back up is the idea behind bass reflex cabinet designs - stick a specific length of pipe in that hole and you get _way more_ low end from a helmholtz resonator.
That’s the first thing I thought about.
Yepp, or hornload the speaker, which many bass speaker cabinets do.
Bass guitar cabs are semi reflex designs. Ported designs tend to be a bit boomy at key frequencies, so bass cabs restrict airflow using a vent with a larger open area (see SWR Goliath or Eden David which have a slotted port at the bottom and sometimes top of the cab). This was a big thing. The first bass cabs were adapted guitar designs, but they needed ridiculous amplification. Then came literal horn loaded PA cabs connected to power amps and rack mount preamps in the mid 70s. More efficient (and smaller) cabinets like the Goliath made it physically easier to be a gigging bass player.
Jim "So I Did The Work" Lill...Thank you for doing what the rest of the internet is unwilling to do (myself included) and what companies most likely would not want to share. This is beyond impressive!!
Thank you for doing the work! The Helmoltz frequency is what describes that "complex relationship between bass response and the size of the opening in the back panel". This is a well documented phenomenon where a hole in an otherwise closed volume can lower it's resonant frequency. This is why sub woofers often have ports. It's also why the size of the hole in an acoustic guitar is very important
Thing is with holes and cuts in the back the aspect ratio of the hole is very shallow so effects like the coupling zone really get to play here. So it's a bit more difficult than a simple Helmholtz resonator
as far as ports... yes and no.
the volume of air inside of a port actually acts as an independent source of resonance. In a sense it is a smaller speaker made of air.
th-cam.com/video/PoEyIJx3uM0/w-d-xo.html
@@Satch_4_Hogs - Thanks for the link!
With the hole you are actually building a ported speaker. Air has a mass and by drilling a hole, you are building a "air-speaker". This is used in subwoofers, to build bass reflex / ported subwoofers. This is also why the sound is falling off in the deep end more quickly.
Those videos are amazing. Love the aspect of actually playing those back to back and comparing them.
Afaiw you need some kind of tube for a ported speaker. Open backs would be more similar to trabsmission lines or rather open baffles, where the increased distance (through the back and around the cabinet) between backside and frontbaffle make the soundwaves from the front and back dont just destructively interfere but might even add up or anything in between
@@torgeeee You don't need a Tube for a ported speaker. The Port can have every form. But of course it has to be calculated (thiele small for example). Depending on the calculation the opening can actually just be a hole in the cabinet. I build speakers in which it has only been a small slit and ones with a rectangle tube/tunnel like opening.
But just by adding an opening you construct a type of "air-speaker", if its fitting for the speaker is of course a different story.
I don't think you can compare the open baffle on the back with a transmission line. The transmission line works more like a flute and is a monster to calculate. This is where you would really need a tube like construction. More so in the Transmission line then in a ported "subwoofer" or speaker system..
I think this is by far my favorite video in this series. Besides musical instruments, my other hobby is hifi speakers. The construction of the speakers determines what kind and size cabinet it should be on, plus sealed vs ported affect on bass response. Your closing statement hit the nail on the head.
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Not too scientific after all! 🙂
Super impressed with the work that went into this video.
Every time you say "So I did the work" it put a smile on my face. You are one of my new favorite channels because of this. Not wasting everyones time talking or theorizing about what might be causing things, or regurgitating what others online say about what causes things. You just put the work in to track down the results, no matter how time consuming or tedious it may be.
I hope you can find plenty of new topics to perform these sorts of tests on for guitar and music as a whole because it's super interesting having all of the myth broken down
The fact that you didn't reveal which was which at the end speaks for itself. You didn't need to because it doesn't matter, they sound so similar that the difference is completely negligible if there even is one. Great work!
There’s more low-end fullness with one of them. They both sound usable but the one with more low end sounds much better to me. Ymmv 🤷♂️
Man when you make a video you go HARD... Fun to see all of this compared. Personally, I play a Marshall plexi through a rather unusual 4x8 cab with celestions, this video again confirmed that I really need to upgrade to a 4x12.
As for the slanted vs straight cab thing, as you said it doesn't matter when you're miking it up close, but it very much matters in a live situation. Because 2 of the 4 speakers are slanted upwards in slanted cabs, they have a much bigger sound dispersion, allowing you to hear yourself better if you're standing within 3 feet of your amp (say, on a small stage), and allowing your band to hear you well too. If you're in the same position on stage playing a straight cab, because of the somewhat limited sound dispersion and your head being above this area, you cant hear yourself well, so you turn up your amp. All the while, your band members standing further away can hear you just fine, so by turning it up you're just pissing them off (ask me how I know).
Agree! As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Just saying! 🙂
So back in uni, I got this good deal on a H&K Tonemeister head. I didn't have enough money to buy a cab with it, but I saw someone selling a V30 for a good price and convinced myself it was a good idea.
Made the shoddiest cab, with a removable back slot, and it didn't sound bad at all.
I remember when building it, people told me that it won't sound good, but watching this has brought me some personal affirmation
“So I did the work”. Heck yeah you did. This was epic. There’s another guy on here, Johan Segeborn, that has a ton of videos comparing the sounds of speakers. Mostly Marshall cabs and greenbacks. But even amongst them there are significant differences in tone. It’s amazing how little attention is paid to speakers and cabinets. When they’re really the key to tone imo. No doubt everything in the chain has an affect. But speakers and cabs are way overlooked for how much they do to the sound.
Johan did some interesting experiments comparing grill cloth material, cabs and wood used for guitar construcion, too. His channel is definitely worth checking out!
How much little attention lol first I’ve heard of it
As just one example, the Boss Katana Artist boasts improved modeling this and amplifying that, but if you put the output of a Katana Artist into a Katana 50 it sounds just like the 50, while if you put the output of the 50 into the Artist it sounds just like the Artist. The difference is all in the speaker and cabinet.
And, as we learned here, that's all in the speaker and cabinet geometry.
Great work - puncturing all those myths that guitar players love to tell each other about "golden tone". Keep up the good work!
This is like Project Farm for musicians. "We're gonna test that!"
uff, i just saw i wrote the exact same thing just now. but yeah, its true
I've been using these videos to teach my kids about science and analytics. Absolutely perfect. I've had plenty of researchers and analysts who are paid well into the six-figure range, who really need to take a few lessons from Jim Lill. Such good work. It's a joy to watch his process.
this is the greatest guitar tone video ive ever seen in my entire life. massive props on the empirical standardized testing with REW and the sheer man hours of building all those cabs!
I can only imagine the amount of work that went into this! While other people criticize your results, you're the one actually testing, and putting in the work while they just philosophize on how you must be wrong. Keep on doing what you're doing. It's very much appreciated.
I absolutely love your scientific experiments, no BS, no "mojo", just measurable facts.
Great work Jim! Of course, it's only a matter of time until they start making cabs out of "toan foam"...and there will be a line of suckers to buy it. As you said, it's just physics. Anything that shapes the sound waves and their path to the mic, shapes the sound you hear in the end. You can get more noticeable tonal change by simply moving the mic around on any given cab than by owning 12 different cabs. Sadly, that doesn't sell cabs, so it is ignored in favor of various and sundry gimmicks. Thanks for keeping them honest. Cheers!
Well...
He didn't test putting sound absorption inside the cab (known quantity where you can look up frequency response for different materials). He could have also tested his idea by using different materials on the back of the cabs. The other big one from the audiophile world is cabinet bracing (hinted at with separate sections within the cab) and even wildly different sized speakers and ports.
It would be interesting to have him pull what he thought was the best sounding cab and try to build something similar sounding at a lower cost (JL cabs coming soon).
this guy is amazing at deconstructing myths. I guess I'm into that.
@@quintessenceSL I think it would be more interesting to get people who think that these things make a difference in a room and do a blind study to remove placebo as a possible source of perceived sound difference
I don't think tone foam would go over too well simply because gear is already easy enough to damage. But this does prove there's nothing wrong with fiberboard for cabinets, except some of the really cheap stuff that smells funny and is probably bad for your health. Many exceptionally well regarded speakers use MDF cabinets with a wood veneer, because the working properties are much more similar on all axes and much more consistent from one piece to the next than with natural cuts of wood.
The low-frequency drop-off below 200hz is from "phase cancellation". The front of the speaker driver's cone directly radiates sound waves, as we all know. What may not be known is the back side of the driver directly radiates sound waves, but 180 degrees out of phase with the front wave, cancelling out low-frequencies. Awesome, unbiased real-world scientific testing that settled alot of arguments. Great job!
bro I just want to leave my thank you here. You have spend a whole lot of time in order to experiment with every single possible config in every single possible aspect of tone in order to spare us the effort. Thanks a lot.
Obviously, lots of work went in to this - not just in building and filming but in all the thinking and managerial work of editing it into a cohesively formatted presentation. Kudos on all of that and the bits that can't even be put into words. As a sound engineer, both studio and live, for 27 years now and a woodworker for even longer I will say a few things that will likely make you want to kill me.
First thing. It's not just the cab, it's the room. Take any cab into 3 differently sized spaces and, using the same amount of power at the same ''volume'', you will get different EQ responses. The diaphragm of any mic can only behave relative to its environment, like a goldfish grows smaller in a smaller bowl but place it into a larger bowl and it will grow larger, it's directly proportionate. Increasing the power to a given cab in a larger space. that initially sounds thin in that space but beefy in a smaller space, does several things that resemble torque curves seen from combustion engines but to the sustain of whatever resonances that cabinet otherwise has. The changes have to do with how voice coils are built and the mass/size of the driver relative to the power and air resistance in the room. The cabinet's construction will either perform great in a 7x11 bathroom or a 16x 24 bedroom or a 3x4 closet, but likely only one of them, and if it does will likely then be trash on a stage. I have my beliefs, I'm sure you will have yours, but there DO exist specific parameters at play as to how to use these phenomena either for or against your patience levels and/or sanity breakdown threshold.
Second thing. Pine or spruce face plates, full-stop. The mid range frequencies at play in electric guitar are very similar to the low mids of a violin. To dissipate them so that none of them ''stand'' you need to avoid both thin/flimsy and dense/rigid faces. The point being you want to reduce cabinet resonance, which do feed back through the face plate, but not leave it dead. I've tried at least 10 different face materials and pine has been the best overall. Double it up to 1.5'' and leave the mounting ring the speaker fits into at .75''. Think about what is going on when a snare drum shell is mic'd (ie from the side). That shell is definitely audible and it sounds totally different than either the batter side or snare side, same as the back and side materials of an acoustic guitar make a difference. The pine/spruce face just sends sounds wave through it FAST and consistently - without adding noticeable ooompf to bass notes.
Third thing. Close micing ain't always it. I've gotten great results at 5' on cabs that just sounded trash within 2-6'' in any space. If the mic is always within 2'' and the volume is always above 95db then don't even bother unless you're just doing a solo performance as any other band instruments will negate 99% of any nuance the cab COULD ever offer. Once you get out around 1.5' the cabinet material begins to matter A LOT.
Dude, you're a lunatic😄 I can't believe how much work you've put into all of these videos. Truly a priceless service you've provided, and an amazing groundwork to build off.
I hope that the message gets through to enough people that they don't need to keep jumping through so many hoops and spending so many thousands of dollars on things that don't affect the sound they're after.
It's great to be able to focus on what really matters.
Yeah, because no one has done this before... EVER. This is the first time... EVER. Now he can invent speaker cabinets for the first time for everyone. You know, if this guy never came along and figured all this out, we would be living in the dark ages still.
@@scottyharris8873 way to be a jerk. Congrats.
@@scottyharris8873 No need to be mean. Of course speaker manufacturers do these tests all day, but they do it behind closed doors. Making this info public is God's work.
@@scottyharris8873 hey, have a worse attitude about something free
@@scottyharris8873 get a grip, dude. How many consumers actually understand what affects the tone in a speaker cab? How much marketing nonsense and baseless myths do most people get bombarded with when trying to buy one?
Don't be a tool.
Absolutely fantastic, good job dismantling decades of marketing mythology. I love this series
Your channel is hands down the greatest guitar channel out there. Thank you for all of the incredible effort you put into these videos!
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Just saying! 🙂
Not gonna lie, I only heard differences for like four of those 12 changes, but that styrofoam cab at the end was an awesome demonstration of the take-home message. Well done sir.
Jim, your blind test right at the end with “which do you think was which?” was the perfect listening test!
I couldn`t hear any difference!!!
@@electrifried Exactly. That's the importance of blind tests. When we already know what we are listening to, we tend to hear what we think the differences might be or what we think should be "better" even if there is no difference. With a blind test our preexisting biases don't get in the way.
Definitely heard more lows in one of them. One of them sounds better. You wouldn’t hear it at all if you listened on a phone.
@@sub-jec-tiv There is no "better", which is not only entirely subjective but also highly context dependent.
I think what you are doing in these videos is just fantastic. You are basically approaching tone with no preconception at all, like a science researcher would do. Awesome.
Jim must be the hardest working man in showbiz. Not necessarily on stage... but certainly in the wood shop. Give this guy a hand to get him the subscriber and view counts he deserves.
60's Fender 2x12 cabinets had insulation installed to absorb some of the frequencies bouncing around inside the cab. This insulation is often used in hi-fi speakers to improve frequency response... would love to see you go down that rabbit hole!
Interesting theory about why the Open vs Closed back cabs sound different. The speaker moves back and forth to create sound inside the cab. In a closed cab, despite not being air tight, the movement of the speaker causes variations of pressure in the air inside, that is, if the speaker moves backwards it encounters a resistance due to positive pressure, and if it moves forward it does encounter a resistance due to negative pressure.
On the contrary, on an open back cab, the air inside the cab flows way more easily in and out, therefore applying little to no pressure in the speaker cone when it moves, and thus allowing it to vibrate more freely, and in general to move "more" back and forth. This phenomenon is more noticeable in the low end, which are the lower frequencies which require a wider movement by the speaker cone.
This theory would explain why the size of the hole in the back also affects the tone, in that it affects the air flow in and out of the cab.
You work deserves a Nobel Prize and you should be inducted into The Hall of Fame!
Please, please keep making these videos! Incredible!
This has GOT TO BE one of the best, most informative vids on youtube land I got to watch the past year.
Mann ! 👏👏💪
This series is legendary. Magnum opus level stuff.
Dang! That's as in-depth a comparison as I would ever need!
Mega props for incorporating frequency analysis into these tests! This is some solid science my guy.
This reminds me of an interview with Mark Bartel who was saying he thinks of his speaker cabs as acoustic instruments and is very focused on the way standing waves inside a cab can build up. Volumetrically, understanding the air movement inside the cab and allowing for it to get out in the right ways seems like fair pursuit.
I'm curious how much these differences apply once you start backing the mic off of the speaker and get more of the room in the mic signal. I'd think the speaker amount and straight vs slant would have a much bigger effect as you start pulling the mic out.
The styrofoam cab was pretty fucking mind-blowing though holy shit. Really gives you something to think about for live situations that are usually only close mic'd anyway, might as well just build a cab that is the best combination of lightweight/portable and sturdy to make touring and setup much easier.
Great video! This definitely took a lot of time and dedication and it shows!
I hope he does a part 2 with room mics to see how much the treble frequencies disappear at different angles.
good point. you saw the paypal right?
"The styrofoam cab was pretty fucking mind-blowing though holy shit. Really gives you something to think about for live situations that are usually only close mic'd anyway, might as well just build a cab that is the best combination of lightweight/portable and sturdy to make touring and setup much easier."
The rub here is that wood is actually a great choice of material if you're trying to balance durability, workability, affordability and weight. There aren't too many other choices that make sense. Molded plastics are one option that works well, which is why you see so many plastic PA speakers and studio monitor enclosures these days, but wood is still favored by smaller builders as they can cut and shape it any way they like without having to involve an outside plastics manufacturer.
Exactly dude botched the point completely by his mic placement.
@@John-e4p1x My favorite was when he put a stick of wood in front of the mic and acted surprised the sound changed.
This video deserves a million likes just for the sheer effort that went into creating it. Incredible. Thanks Jim!
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Just saying! 🙂
I’m currently building a 212 cab, and I’m using this video as reference. Thank you.
I’m also an engineer, and your “Design Of Experiments” (DOE) method is almost exactly like what I have done. DOE is GREAT at finding interactions, relationships, and thing that have little effect. Nicely done.
I play guitar probably one every other month - these videos are still instant watches for me. Great stuff.
well - not only did you do a LOT of work, you also had a method to what you were doing and are good at explaining what you did and point out the results you felt/got. Excellent job!
These videos just keep getting better and better. The amount of work that goes into the experiments is one thing, but tracking every result, organizing it, and presenting it via brilliantly executed audio/video cuts is extremely time consuming and labour intensive. I'm excited about where this channel will take us as you move on from guitar to Pro Audio in general. I think it's important to mention that your content is not only highly entertaining, it truly is a public service. Thank you!
If there was a Venn diagram of Dedication vs. Scientific Method, this guy would create a perfect circle. Awesome job!
These are honestly the most useful TH-cam videos I've ever seen. Groundbreaking. I can't thank you enough.
This video is exactly why I like TH-cam and all the amazing people who make such awesome videos for everyone to enjoy and learn! Huge thanks, man, it’s really cool!
The strips of wood on old amps are diffusers and disperse the treble frequencies wider in the room. The treble frequencies gradually disappear the further you move off-axis from the speaker cone.
One huge thing that wasn't tested is the sound in the room as opposed to right in front of the speaker. For recording, a 57 right in front of the speaker is absolutely valid. But the vast majority of the sound when you have a cab in the room comes from the sound being dispersed at an angle.
The strips of wood might make it sound a bit too dull in comparison, but they actually remove the "icepick" effect that is caused right in front of the speaker, basically making the speaker have a more balanced response at a wider angle, and therefore a smoother tone for more people in the room.
@@distortingjack I agree that he should have recorded the room at certain angles. My band played a gig a few years ago and people on the sides of the room were complaining that they couldn't hear the guitars. It sounded fine to me, but I didn't realize that the treble frequencies disappeared tremendously for the folks sitting on an angle.
I did some research on dispersion and diffusion (duct tape, beam blockers, Mitchell Foam Donut). On my 1x12" combo, I taped a 6 inch piece of very thin foam (3mm) in the center, with a 3/4 inch hole in the center. The small hole in the middle acts like a tweeter and spreads the high frequencies very evenly...no more treble beam of death coming from my amp!
I rarely comment on videos, but this was excellent work, so it deserved you knowing it. I can't wait for more of these tests. Keep up the great work!
Wow, we appreciated your high commitment. We all know we're buying cabs for the brand.. well, they sound about 90% the same to be honest depending on the ports & speakers.
Can't wait for the speaker video. Looks like as long as a good speaker is screwed to a big enough box it's gonna sound alright.
"What if we don't hear the cabs resonate" at 17:24 was a home run for me. I make flutes out of materials like PVC pipes, and people are often surprised that they sound really good. The reason they sound good is the same as in speaker cabs - the material doesn't resonate audibly, only the chamber of air inside does. In a flute it's the smoothness and straightness of the body, the geometry of the finger holes, the shape of the mouthpiece etc., that shape the tone. (Which makes PVC great because it's manufactured with consistent geometry. I don't have to be nearly as skilled as if I was making them from bamboo).
The one caveat is a material's dimensional stability does matter; an instrument that changes less in response to temperature and humidity will be easier to play in tune and maintain its tone better. I imagine that in a speaker cab, the dimensional stability of the material could affect the geometry and therefore maybe the sound as well.
Cab resonance happens with Bass, not with guitar. Run 400watts of power into a bass cab and you can hear resonace.
@@crazyjack9voltbatteryamps Clearly, if you've heard live Bass at stage volume, you'll hear cab resonance and speaker compression. The effect is much greater with Bass.
Solid wood does resonate, plywood less so, and mdf almost not at all, which is why many even high end audiophile speakers are made of mdf.
This is golden. You deliver every time Jim ! And it just confirms my years of studio experiments : the "magical" cabs are the ones that have the right mix of speakers vs geometry.
How they're made and what of is a practical and aesthetic consideration but tone-wise : no significant change.
As an amplifier cab builder myself, I have to say that this video is somewhat misinformational: If every audio clip in this video does actually correspond with the visual/video presented on screen, then it is clear to see that the recording microphone (in 99% of instances) is directly in front of the speaker... so, in a 4 X12 test... Jim is only recording ONE speaker... same goes for a 2 X 12 or any other combo. The wood, resonance and structure of any cabinet DOES affect the tone... but you're not going to hear that with a mic placed right in from of ONE speaker. To do this properly, Jim should place the mic say... 20 feet away - about where you'd hear the speaker if you were stood near the front in a small venue.. or managed to get right to the front of a stadium gig. Just saying! 🙂
Ideas:
-backwave reflections from the inside will cancel and reinforce different frequencies depending on distance from the speaker. Try changing the depth of the back panel so the cab get shallower and shallower.
-also try adding damping materials to absorb reflections on the inside. One surface at a time, then pairs, then all. Absorbing direct reflections will make things different!
-loose polyester fluff from a pillow left in the cab will absorb low end resonance by converting the vibrations into heat, and it slows down the waves enough so the cab behaves like it's bigger (but with less bass). A boomy cab can be tamed this way.
-try to angle the back panel or baffle more and more and see how the gradually less direct backwave affects the frequency response.
-surface mounted vs inside mounted speakers supposedly changes things a lot. Interesting?
Give a medal to this man. Proper science.
Seriously one of the coolest things I’ve ever seen on TH-cam.
Dude! I always LITERALLY laugh out loud when you build or do something crazy that is supposed to affect the guitar tone and then doesn't! F*&king Awesome man, really, thank you for doing this so we as players don't get caught up in hype and marketing.
I definitely recommend watching the channel Tech Ingredients, if you want to learn more about the physics of speaker design. They do a fantastic job of practical demonstrations of the science and engineering behind many things. From constructing their own drone, to making their own thermal paste.
100% agreement!
My buddies in high school all had subs in their cars and one thing I noticed was a massive difference there is between a poorly home made sub box (cab) and a legit one.
At the most basic level the reflected waves matter the same as pushing someone on a swing. The wave reflecting off the back of the box wants to hit the subwoofer as it’s going back out and ride pushing it out not when it’s coming in and clashing with it. It gets more complex than that but it’s a good starting parallel.
You can cheat a little if you pack them with old clothes.
All different sizes of speakers will have a perfect size cab for volumetric efficiency and it will depend on whether they’re sealed or ported as to what that number is and how big or small the box should be.
@@lathiat That's not what's happening with subwoofers, the frequencies they're dealing with have much much longer wavelengths - subwoofer behaviour can be modelled using Thiele-Small parameters. However that rear wall reflection can have a significant effect on midrange response and is one of the differences you hear between typical closed and open-backed guitar cabs.
this channel continually blows me away with the level of dedication to testing tone.
i love how when cutting holes in the back baffle you basically rediscovered porting lol, but this video was great!
Thank for for doing the work. All that work!
(Now I'm torn. Do I wish well for Jim by hoping his music career takes off, so that he has no time for videos, or that his TH-cam career takes off, so we keep getting fantastic videos from someone that actually tries stuff rather than just talks about it, even if that leaves him no time for making music?)
Incredible video.
I would literally pay to see this experiment done for bass cabs.
Amazing work! Thank you. I think using a second mic somewhere away from the speaker to get more of the cabinet sound would be helpful. By only analyzing the sound from a mic placed closely to the front of the speaker, it eliminates the ambient sound from the cab in the room. Having a second mic that is placed to pick up room sound from the cab would be informative. Of course, you would need to control for variables in the room, eg, placement of cab, mic, same room/space with no changes in other items in space, etc. An isolated and controlled space.
This video is absolutely legendary. What an amazingly thorough experiment you've conducted here.
I had to subscribe, it was the minimum I could do after watching all that effort.
CONGRATULATIONS, thank you and bravo!
Another great video! Really love your scientific approach on all these experiments.
Love your videos and love your premise for each one. I'd love to see in a future episode what affects pickup tone. Why do they sound different? The magnets? The ammount of winding?
Would the difference in tone be more apparent with some mics set further back ? Anyway really cool seeing you go through the cabinets so objectively and edited to make abrupt A/B comparisons. I know how a certain responsiveness and tone can inspire one to play more. You really dug in and tried exploring so many aspects- really great thing to share. I appreciate your empirical almost scientific approach, only changing one variable at at time etc.... And nicely produced to boot. I am impressed.
You’re a mad scientist, brother. One day, your contributions to audio science will be recognized.
The Adam Savage giggle when he uses the 11’ hole saw was pretty wholesome.