I recently made a TH-cam short about flat response in-room vs anechoic and asked if anyone wanted me to expand on the topic in a future video. The response was pretty positive so here we are. I hope you find this informative. I also hope the next time you see someone make the same mistake of thinking they’re the same thing that you can use this video to help them understand why they are not. It’s not just people on forums. I’ve seen many audio influencers/reviewers show this same misunderstanding. There are many caveats to a topic like this, but those caveats are a rare exception. This video is not intended to be a deep dive into the caveats and certainly not intended to make the statement that my discussion is always the case. It is intended to be a 30,000 foot view of the topic. If desired, I can create future videos which will dive into the topic a bit further. For now, this is the jumping off point.
You mean videos WAY off the mark that drive me nuts like this one? th-cam.com/video/r1IhzuGDkkA/w-d-xo.html Your video is logic and reasoning to my ears. Pun intended. Literally scientific. That other video drove me nuts. Thanks , so so much for all you do Erin
I also had the problem with my speakers and I figured out, that simply listening to a slow frequency sweep and properly equalizing the percieved loudness of all frequencies for each channel individually gave me the best sound quality and clarity. Tried 'flattening' out the response via a meassurement mic and while the mic said that it was good, everything just sounded awful to my ears.
@dreieinhalbeck1528 I guess that's the perfect way to do it. I'd assume the mic is the perfect way to make it all "flat" or be able to tune it to your profile. The thing is, we listen to the end result with our ears, which are either not perfect or we may not actually like that "perfect" sound.
I knew a lot of these concepts from doing research and watching videos over the years. But this is the best and most concise explanations of all of these concepts that I have ever seen/heard.
Odd that it hasn't been elaborated on as much as each speaker will have its own unique in-room response based on its dispersion pattern, and that really underlines why measurements are essential. You have to have some idea of where it makes the transition to the listening window before applying EQ, especially when subs are involved. Need to know where they need to intersect the main part of the response in order to blend in properly. Being a nearfield user, I had to work this out myself years ago when setting up systems since its much easier to use measurements to build up what the in-room response needs to look like for larger speakers rather than just doing it by ear. If I recall Sean Olive had the rather bland comment of "its because the sound is comprised of both direct sound and reflections" on ASR which wasn't too insightful.
You explain things perfectly for me. I had so much information already in my head but didn't really see the full picture, until now. Thank you Erin, much appreciated 😁👍
Great explanation of room response. I recall when taking speakers outside for a party and the bass response was so thin. I can see why pro audio uses many large bass cabinets and a lot of power.
0:05 "Flat anechoic is not flat in-room response". "You basically put a speaker into a container." Unfortunately, some containers (rooms) are better than others. 5:06 Shocking what happens once you put a speaker into any room. 7:53 so you typically get enhanced bass and tapering treble? 10:24 The speaker dominates the sound above 400 - 500 Hz. Below that the room dominates the sound.
Great job ! I have seen several of your videos and have decided to subscribe. I am glad that you are bringing some science to this otherwise subjective field. Too many vendors out there selling products that exploit the uninformed consumers
What about near field response? For example, various near field speakers that measure flat on axis will measure almost completely flat in a room measurement taken at 1m distance.
Great explanation, and I love what you’ve been doing for audio enthusiasts. I would only say what I also believe to be correlated with what Dr. Floyd Toole called “the circle of confusion”. In theory, if all recordings started (many decades ago) with speakers/monitors that measured flat in room, all the mixing, EQ and even microphone placement/response would have to be tailored to sound good with that response. But that’s not how it started, and it would be a lot harder on the earlier recording equipments to deal with that added bass (that would be necessary to sound good and balanced with a flat in-room response. In any case, it’s too late to change how it all started so many decades ago, and making a loudspeaker to sound flat on most rooms (and even studios) would be a moving target, and the anechoic measurements should be more consistent. That being said, it’s still a moving target, as most recordings were made on very unique playback systems (mainly loudspeakers and studio acoustics), and most well known studio monitor manufacturers were clear on measuring how much different the same monitor model sounded on different studios (that is often the base for advertising how much their room correction features will help on trying to level things out, but the fact remains). It’s also not uncommon for loudspeakers that are considered a “reference” on some studios (like Abbey Road and B&W 800) failing to be flat even in anechoic measurements (even in the mid/high frequencies), which doesn’t stop them for being widely used for mastering. The same can be said about the famous “BBC dip” deliberate response, that we can agree or disagree to be a good or bad thing, but it would be hard to ignore that we’re the reference used to mix many recordings over decades. IMHO, an anechoic flat speaker with controles off-axis response does have the _potential_ of sounding best with different recordings, but not necessarily with all of them, and this goes back to the “circle of confusion”…! If a mastering engineer used monitors with the “BBC dip” in the most sensitive audio range for vocals and “presence”, either he was able to compensate for it with the accumulated experience (which definitely was the case for some of the greatest), or playing it back on a flatter loudspeaker response in the range would end up like a “BBC peak”. 🙂 Most subjective audio reviewers used a wide range of recordings to “evaluate” loudspeakers, often introducing even more inconsistencies (how can you compare two loudspeakers with two different recordings?). But even if any reviewer chooses to listen the same predefined tracks for loudspeaker evaluation, the question still remains: - Why does he/she use those particular tracks, and not others, that would sound worse on flatter anechoic loudspeakers (but maybe better with less balanced speakers, maybe closer to the ones that the record was mixed/mastered with? 😉 I’ve been in the audio business for some decades now, and I made several audio demos, and was the listener of many others. Making any good audio demo implies taking the time to try what tracks make the loudspeaker shine, and a particular loudspeaker will usually have some specific tracks in order to accomplish it (sometimes it can change depending on the room’s acoustics). While that may seem like a biased way of making a demo (and it certainly is in some ways), what happens if the prospective buyer happens to listen that kind of music and recordings? There are certainly very audible cues on music genres (hard-rock or heavy metal tend to have less bass than jazz or hip-hop, pop vocals are mixed in a different way on every decade, etc), which makes a challenge for any loudspeaker (or headphones) to sound great across such a wide range of sonic signatures in the recording itself. This is one of the reasons that makes me believe that removing even the most basic tone controls on amplifiers was far from smart, with audiophiles believing that they would be closer to the original recording by avoiding the circuit (and ignoring how much “EQ” any loudspeaker and room will end up introducing on the sound that reach their ears)! Maybe that’s the reason why loudspeakers always fascinated me the most on any audio playback system, since they all end up introducing their own sound signature, and while some recordings may sound their best with a particular loudspeaker, other recordings will sound best with a different loudspeaker (within reasonably well behaved loudspeakers). Let me reinforce how much I value objective data, and trying to understand the correlation between measurements and what I can hear. I’d say that actual anechoic measurements are the only reference point that doesn’t change, since once we put the loudspeaker in a a room, it can work with or against it, and no reviewer is going to listen to a loudspeaker inside an anechoic chamber for a subjective review (and it would be worthless if they did). But in the end, and like you said, measurements are useful for making some baseline comparisons that may be helpful at selecting an comparing loudspeakers, but we still need to listen to them in our rooms, and with the music that we consider as good reference points for the music we listen the most. In the end, finding the “right” loudspeaker for us (and the our room) is still a moving target for several reasons, and until now, the best compromise that I could get is to have more than one system (with different loudspeakers) around the house, because some records make me want more rolled of highs (it sounds more “comfortable” on longer listening sessions, while other records will sound more exciting and interesting with more highs (giving them a sense of a lot more detail). Measurements are the only objective way of comparing loudspeakers against a fixed reference, and that’s huge. S But loudspeakers are simultaneously the less complex equipment on most audio playback chain (from an electronics perspective), but also the most complex “device” to make it work with every room and musical preferences. There are so many different amplifiers that sound pretty much identical, but it’s virtually impossible to make to different loudspeaker designs that sound nearly as identical between them. And I’m not sure that it is ever going to change, just like the same orchestra will never sound same on different concert halls. 🙂 I don’t have nearly the same passion for amplifiers (let alone dacs), probably because if an amplifier or dac makes such a significant difference as two different loudspeakers, one of the amplifiers need to have a terrible design or fault (aside from power, if we push them outside their limits).
Ok so flat response is the target curve of the speakers themselves (measured in an anechoic room), but then, what is the target frequency response of a room? You say it that curve would have the bass elevated and the highs decreased, but is there a target curve that exists in all studio rooms that we can try to get close to, precisely measured?
Great question. I know this is covered in Floyd Toole's Sound Reproduction. There is no rigid target curve because studios and domestic spaces will always vary. The idea is to have absorption/scattering evenly across the hearing spectrum (diffusion isn't possible in such small spaces), fix room nodes etc. An anechoically flat loudspeaker always translates well in such a listening space, and roughly speaking, the target response will gradually slope down from the bass frequencies toward high frequencies. Takeaway is to buy an anechoically flat loudspeaker, set it up well, and don't use room correction software to flatten the response, except for a couple of room node low frequency peaks.
@AvithOrtega the curves aim for 'natural' not 'studio' sound when it comes to speakers and headphones. there is no such thing as precise 'studio sound' just like there isn't one for 'concert hall'. each studio and each concert hall have different characteristics (less variation for studios of course). in studios the important thing is familiarity (according to sound engineers). w/ enough experience/familiarity sound engineers can predict what the audience will experience and they try to match that to what the artists intended.. their tools are aimed to help them detect potential issues not necessarily to make an enjoyable listening experience. sound engineers often use monitors or presets that help them 'magnify' fq ranges they consider need extra attention, much like using a magnifying glass. as such, 'studio sound' is not as pleasant as ppl like to imagine. same goes for recording rooms with the most drastic being the 'booth' for voice recording. in such 'quiet rooms' the sound is truly unpleasant as it deviates a lot from our day to day experiences of hearing noises and sound reflections. ps: as @shalinkochar1081 mentioned, for all intended purposes, we the listeners will never hear the finished recording the engineers/artists heard when they decided it is ready for release, regardless of the room and sound system we use. a great sound engineer once said 'if one wants to hear in high fidelity a recording of a live concert they need to listen to it outside on an identical PA system and if they want to listen to a studio recording they need to build a room identical to the studio and use the same equipment'.
@@shalinkochar1081 The problem with Floyd Toole and Sean Olives approach is; for the most part they're not targeting audiophiles, they're targeting consumers. That's the success of the like of Bose and Harman group. They may have the odd product for the audiophile, but in most cases it's boom boxes, decidedly average car audio products, but they're targeting people with average income, that want to have a bit of sound in the kitchen maybe, and they want to pretend that their equipment is good, enter quoted high wattage numbers, flashing lights etc. I take Floyd Tootle's approach in the realms of what he was paid to do, rather than a ROT!
It should be noted that this happens to live instruments in any given room too, which is why in-room response is what humans expect to hear. This is also why I enjoy near-field recordings over concert recordings, so I'm not "doubling up" on the room ambience.
Wow! Very good informative video. You explained it in a way that even a child would understand. I now understand why Audioholics recommends the 500 hz room correction. Looking forward to more videos like this on some of the technical side of home audio. 👍🏽
Great video, glad you're back. I bought the IN-5 thanks in part to your reviews! I'd love a video where you'd explain how to do proper room eq (and what not to do). Thanks for the videos.
Super explanation, Erin. You could probably do a part two regarding absorption in typical listening environments which make this anechoic to in room difference even bigger. And for good measure what it takes for anyone trying to manipulate/improve acoustics in the bass....
Yes I would love if you made a part 2 explaining sound absorption and how it works. Also, if audyssey, YPAO etc with sound absorption is better or turning audyssey, YPAO etc off with sound absorption is still better .
There’s a great you toober on acoustics. Yesco. German guy.. sorry I cannot think of exact Chanel name. Even then it’s pretty nebulous feeling how to treat fir lower frequencies.
@@chinmeysway He's good. He writes his name Jesco, and the name of his channel is Acoustics insider. He does, however focus on studio design, rather than home audio, and for the most part on nearfield listening. If you go his way, you will arrive at a very dry representation, very fra from what Erin would prefer. But yes, Jesco appears to be very competent. And I believe that he'll have a bunch of things to teach even to those preferring a more wet/reverberant reproduction.
What a great explanation! I tried explaining this on another channels comment section. You did a much better job! Btw your objective scientific approach is very much needed, I wish you as much success as possible you deserve it. The work you put in is much more valuable than the sea of subjective feelings they have about audio equipment.
Hi Erin, can you please elaborate on WHY measured-flat in the room is bad? I'm guessing if you measure a linear monitor at near field, it'll be flat. What's wrong with correcting room effects that cause a downward slope in response? (and that's not limited to 500Hz btw)
Imagine your voice. We can say that you have a flat response of yourself (you sound exactly like you :) ). Now imagine you are being recorded in a studio with no room sound. Now lets move to a living room with typical room sound. If you start speaking, one can hear you and the room. This is considered your real voice, since you never speak with people in an anechoic room or a studio, so this is considered you. Now lets take the recording, which is you minus a room. If you play it on an anechoic flat speaker, then its: (you - room) + room = you. If you play it on an in-room flat speaker, its (you - room) + room - room = you - room, which is you sounding like a tin man.
@@okosakaroklenni A few questions: 1. Why is it ok to correct what the room does at lower freq but not at higher freq? 2. You're effectively saying listening with near-field linear monitors, or accurate headphones, makes you a tin man since a room doesn't modify the sound. I dunno about that. 3. Every room is different, and by not correcting its effect you won't hear the intended tone balance. Isn't the masterer using linear near field monitors?
@@f7i6f67fkh 1. You want to correct what the room does at HF. Its not about frequency response, but an even reverb time, so you don't f*ck up power response. FR is not really affected by the room. I mean it's too chaotic, you don't really hear the comb filtering. 2. About headphones... I had a very linear headphone, and hated the sound of it. you can get used to it, but don't really want to. Except of course if it is your thing. Near field monitors still have the room sound, you only get rid of early reflections. But SBIR from the walls and especially from the desk is a real problem. 3. The sound engineer is mastering for a target "audience". And you don't really want to listen to music on a gear like that. +1: completely EQ-ing out the room to a flat response is not the same as treating the detrimental effects of the room like long RT, giant 20dB canellations and early reflections. And it's not the same for a studio, where you need a standardized sound for professional work, and a listening environment, where good psychoacoustics is important. At least this is what I think, as I'm not a professional, just read a bunch so that I could treat my room. Also this is what a professional engineer told me when measured my gear. He told me I want the speaker linear anechoic, and then add an even room sound.
@@f7i6f67fkh 1. acoustic room treatment covers a wide range of fq. for higher fq a combination of absorption and refraction/scattering is used. as the fq decreases it becomes more and more difficult to absorb and impossible to scatter (redirect) and that's where the shape of the room is designed in such a way to minimize 'room modes'. in short the ratio of LWH and angles play the largest part. for professional purposes, rooms are designed/treated for a rather low reflection* index not for 'sound quality' but for analytical reasons (so the engineers have an easier time detecting what does what). w/ that in mind, it is often the case before a mix is finalized and sent to mastering, the recording is auditioned in other environments outside the studio in an effort to check if the intended tonality/vibe/etc of the recording is maintained for as many possible listeners as possible (some listeners will listen/enjoy the recording in their cars, kitchens, livingrooms, etc) *they do not aim for 'zero reflections' because such a room is fatiguing. being so different than real world audio experiences our brains have to work overtime trying to understand the surroundings as there are no reflection cues to analyze (can't tell the size of the room, our position in the room, etc). as the brain works in the background extra hard, sooner than later the listener will feel exhausted or even stressed.. 2. all those devices account for our preferences, a response that seems natural to us. headphones have an inbuilt fq response that is rather chaotic but based on studies produce a balanced/pleasant sound. same applies to studio monitors. in fact most of them have settings (some models jumpers or switches to "EQ" their fq curves based on the environment they're used in and some offer those presets in their menu). that being said, those devices are aimed to help engineers detect easier/faster issues w/ the recording, mix or master. their purpose is not necessarily to sound natural. for that reason many engineers develop a workflow that involves checking their work using different sound sources. the ultimate goal (and it's an impossible task) is to make such a recording that sounds like the artists intends to every listener. a good engineer is one that understand what the artist intends and is able to shape the sound is such a way that a listener in their car will get the same 'vibe' as one who listens to the recording in their bedroom. as you can imagine lots of compromises and tricks need to be deployed for that.. 3. when mastering, just like when mixing, the sound engineer checks for issues. that's where the main efforts are concentrated. next is obtaining a vibe that's as close to the intended vibe requested by the recording artist. finally, they try to shape the sound in such a way that it will maintain some of that vibe over a wide range of listening environments and devices. many engineers say 'linearity' is not as important to them as 'familiarity'. that means they choose tools that offer them the best chance of predicting what the recording will sound like for the vast majority of listeners and because none of us hear the same things (in fact out hearing changes w/ age, time of the day, mood, etc) sound engineers prefer tools that work best for them (hence not all studios use the same monitors, say the 'best' monitor available at the time even though some could afford any available monitors). monitors offer presets that change the character of the sound, some deploy very drastic changes such as making a 4way monitor only play two of the transducers in a 'full range' manner. this shows how much effort is put in trying to make 'everyone happy'. in effect they are trying to 'guess' how the recording will sound for ppl... the more experienced an engineer is, the better their 'guess'. real good ones can not only make that 'guess' but also have a feel for what a certain audience target prefers. it starts w/ the recording engineer and end w/ the mastering one... in a 'perfect world' there would be multiple mastered releases for the same recording. one for listening outside on the pool speakers, one for headphones, one for powerful home theaters, you get the idea. but that's impractical. so in reality regardless of the room and sound system, we won't ever hear what the artist heard when they decided the work is ready for release...
Great explanation. Thanks Erin! My lightly "treated" music room had massive bass modes at 27 & 54hz. A DSPeaker Antimode preamp eq'd them to flat. The result sounded pretty anemic, so the instructions recommend raising the bass level afterward. Better.... Currently not using any eq with (dipole) Maggie/REL and occasionally Rega TL speakers. You learn the sound of your room. But make it as comfortable as possible before you add speakers and music:-)
Thanks Erin.. Only been watching for month or so.. I've learned so much. You have a great way of explaining things in my opinion..I understand and realise I'd like to learn alot more.. My budget is more a diy build.. My sound space/living room/kitchen Annex is relatively small. And long. I'm aiming to build a great home theatre.. /hi fi stereo.. My listening is about 50/50.keep hearing that I have to make better half happy while still treating the very reflective room.. Love your vids... Thanks..
Great Video Erin!!! These are the types of videos that Make it All make Sense. I love these, Even and Old Dog like me can learn something, Keep up the Great Work!!
Great explanation Erin. I’d very much like it if you were to get together with Danny Richie and give feedback on his system and what he does, as Jay of Jay’s Iyagi and Chris from Vinyl Attack have done. I find your videos very informative and find they complement what I’m learning from Danny’s videos very well.
Also needed is survey of how companies test for sensitivity rating: is it in a room/ room size, is it outside, is it anechoic, do they round up to much regarding room gain etc etc
In the early 90s, I graduated college and bought my first speakers. I bought a pair of Infinity Advents, because they were the “flattest” speakers I could afford, per an article in Consumer Reports. Despite being “flat”, I turned the treble up a little, and I turned the bass down a little. As I learn more about room acoustics, I’m wondering if that might be because some of the highs get lost in the furniture and some of the lows gain from the walls. With that in mind, I’m also wondering if it doesn’t make sense to look for speakers with a little bump in the highs and a little roll-off in the lows.
Flat response is in relation to input signal at x dB across entire frequency spectrum. The music we play it’s not linear so we won’t hear flat sound because you have calibrated speaker to have flat response in your room - for specific sound level. True under 500 is critical where the room dictates the sound but it doesn’t mean if you calibrate rest of the spectrum, then it will sound dull. It can correct unwanted peaks, fill in small dips. DL does it well, Audessey has tendency of sucking life out of sound because it does a poor job at determining room interaction and applying correct filter.
Now you've said it all. The various speakers I've had in my room always measure more or less the same in my room. Instead of spending money on speakers, spend it on the room.
So, my last post referred mainly to high fidelity, 2 channel rooms...whic is hard enough to treat to flat response. Most here are HT/AV, but with so much more LF and with multiple speakers, a flat room EQ is even more challenging, and more expensive, and theaters are usually small rooms, less than 30 x 20. However, the same general methodology applies as in higher end 2 channel listening rooms.
I like this kind of videos, where you dive into the matter! One remark. You said that with an omnidirectional speaker the anechoic response and the in room response are the same. In my opinion omnidirectional speakers don’t exist. The speakers that claim to be omnidirectional are only “omni” in the horizontal surface, not in every (omni!) direction!
Good thing that most decent amps has bass and treble controls. Now you know what they are for. We knew this in the 1960s, then everyone forgot what good equipment can do and sound like. In the last two decades, designers spent less money on the R&D electronics and more money on the aesthetics with gold plates sockets and included as much weight as they can to give the appearance to be better and sleeker and of course much more expensive. Those days, I remember a top system (as described in Hi-Fi News) Includes a turn table, Like Linn Sondek, Thorens Rega, Pink Triangle, top-end cartage, like Kutsu Black, Dynavector Carat Ruby. Lin ASAK, Shure V15, etc. excellent tone arm such as the SME, Linn Itok, set of three-way floor standing speakers'such as the KEF, Rogers, Spendor, B&W, Cellestion, Richard Allen, etc, the best amplifier money could buy, including makes such as Pioneer, Sansui, Sugden, NIAM. Kenwood, McIntosch, Marantz, Luxman, etc. all for the mighty sum of 1000 British Pounds. Now is a good time to donate that new amp, micro sized 4 inch speakers, streamer and DAC that you bought to the salvation army and get yourself something vintage from the 70's or early 80s and really start to enjoy what we had access to in the days past. Nowadays, you get a single knob, including a plastic remote control, pint sized speakers and power bricks, all sounding like crap but costs more than a half decent house, only to be compelled to upgrade each for something with a smaller driver, bigger knob or LCD each time a neighbour buys something more expensive.
I wish the recording labels released their recordings with a variety of differently mastered equalization options to choose from. That way, we could select a version of any particular recording that best suited our HiFi system and room response, without needing to adjust our system settings (distorting the frequencies), to get closer to a true flat response result. Even a choice of 3 different versions would be helpful.
Thanks. Very helpful. It’s always a bit challenging for non techie home audiophiles like me to sort out home audio acoustic treatments and EQing. A lot of trial and error and frustration. But it is so satisfying on those not so often occasions when I do finally get it right. Or do my ears tell me.
If your ears don't enjoy what you hear, then no matter what "acoustic treatment"or EQ you apply, or whether your system is hyper expensive, you have actually wasted your money. 🤥🤥
I think that is where Erin really shines. He can explain things to the lay person in a way they can understand. I like to watch Amir as well, but I have an engineering degree. His explanations can get a bit technical.
Reducing the peaks and leaving the dips alone is a good advice : the peaks can be anything (even not speaker, it can be something vibrating in the room) I got my best results by just putting pink noise, and insuring I get the bottom note around 85db, then I eq the peaks down and insure I have a nice slope to 16-20 khz, usually there I am between 77 and 80 db (on tweeter axis V pointed at the mic) . So the fight is more with room modes and objects and glass and eventually some issues with the speakers, but mostly room. And to do the eq well you need everything playiong : both speakers and the sub. Because eq changes if you cut any of them. Eq changes also if you move the crossover. Eq then and get a dip or a peak elsewhere. That's a living room, not a lab.
This makes alot of sense... my dad is having an issue with low frequencies in his room (it's a dedicated room) he was told he should deaden the room with panels and pictures on the walls... is it possible the room is too dead and that's why there's an issue with thin sounding bass? Speakers are KEF R11 towers with (2) 12" subwoofers The room is 15X18
I was thinking this the other way, our ears are less sensitive to low frequencies and more sensitive to high frequencies, our ears are no professional microphones
Erin - I have to say this is the best video of yours that I have seen! Excellent coverage of a complex subject. I wish you might have added a *bit* more about *why* drivers become directional - as the wavelength gets shorter and shorter, and approaches the width of the driver - it becomes more and more directional. I.E. it gets narrower the higher the frequency; and becomes a "beam" when the wavelength is smaller than the driver. I like the ripple tank illustration. As complex as it is - a room is obviously 3D - and so the wave patterns are *even more complex*.
I did and I had graphs. But I edited that out because I really wanted to keep this at a high level. I know if I get into the weeds then that may push the casual watcher away. My main point is for the viewer to understand that flat isn’t always flat. I’ll likely make some follow up videos to this, though, and will talk about those aspects, referencing this video as the jump-off point.
Nice explanation Erin. It reminds me of a time when I first bought my new shiny RTA and I set out to force my sound system in the trusty Escape (using high-end Morel separates, DSP, Rockford Subs, tons of sound deadening...anyway, done right...not a wing it on a weekend install by any means). I was so excited when I had that response looking like the "JBL reference curve" with the gradual downward response toward the high end. I rushed to get in to listen and it sounded hideous. I mean, it sounded worse than having all DSP settings flat and just letting it do it's thing. What I learned made the most sense was to only cut peaks and limit boosts to 2 dB. Anything that boosted screamed "HERE I AM" when you sat in the car. Anything cut was "out os earshot, out of mind". I could never resolve that pesky midbass cancellation issue because standing waves don't respond to boost or cut but that's my story. Your explanation is a concise version of a very hard lesson it took me a while to learn.
Great video! Dumb question: Is the front wall behind me or behind the speakers? I think different reviewers might be referring to the front wall as the wall directly behind the speakers. Ex."I set up the speakers pulled out 3 feet from the front wall.", while review measurements refer to front/rear wall reflections. THANKS!
It’s super confusing, I know. So.. In the SPINORAMA data the reference is the speaker. So “front wall” is the wall in front of the speaker. Which winds up being the wall behind the listener. For my sake, I wish it wasn’t labeled the way it is but I understand why. It’s just awkward to talk about the speakers front/rear wall vs the listener’s. 😂
So I understand that direct sound being flat above transition frequency is most important. The angle comes from early reflections and sound power, not direct sound being altered?
So, is it right to say that use of acoustic panels and bass traps is useful in that they address stacking of LF, but one needs to be wary of EQ-ing the sound to get a flat in-room response?
If anyone here mixes / masters tracks I'd be keen to know what curve is targeted in studios. Is there a standard for this, or is it down to the preference of whoever mixes the track? I always assumed a flat curve within a couple of dB was the goal, so tracks would be mixed to sound best with a flat response. Perhaps a realistic but still smooth in room response is targeted, to be representative of a typical "decent speaker" in a typical room. To add a layer of confusion, 90% of songs will either be listened to on airpods or in the car with additional signal compression applied over the radio. Must be a heck of a job to choose how to mix a track to sound decent in the most scenarios.
What if the measured response is sloping upward (no EQ)? Does that mean the response is nearfield dominant? Would you EQ the treble down at that point?
I learn more from your videos than I’ve read in the past 50 years. Speakers that are expensive and have boosted highs and lows then get rave reviews just confuse me. I prefer a flat anechoic response. Then fight with the room.
Thank you for your awesome video. How much roll off or taper (in dB) should a great speaker produce when you do an FIR graph with REW? If an FIR graph shows the speakers are too bright can you use EQ to roll the highs off more? I know you say not to boost the lows, but what if when doing so you get lucky REW is showing a better response curve? In that case is it OK or still never boost the lows? Thank you for your knowledge!
Companies must mostly measure things in non anechoic rooms I’d assume though so it’s all really non conclusive. Any guidance on that would be lovely. Are there any stats on how many companies / which ones measure at all of anechoically?
Excellent video!!! I struggle to explain the same to people - I’m just gonna point them to your video from now on 😊. I was gonna add that maybe it’s worth pointing out that higher frequencies are more easily absorbed (e.g., sofa, carpet, curtains, etc) then low bass, and are less likely to “build-up”/“reflected back” - and thus further contributing to the overall downward in-room response tilt.
Hi Erin , how do you know when we can equalize a speaker and what are the frequencies that can be adjusted using inclusive parametric equalizer. As i understand from one of your videos frequencies below 200hz could be adjustable but I think the mid high and high frequencies when you adjust these we can change the tone characteristics of the sound . When the room correction systems as Dirac an others can be applicable without changing drastically the tonal quality of the recording . To me we have to start with room treatment that in many cases could solve the problem for mid and high frequencies and use the equalization to correct the room node modes. The correction room systems works in all the cases or have certain limitations. I see some reviewers using pro DSP parametric equalizers to solve room problems but this i think does not solve all the problems Thanks for your response
Thanks so much for your well explained video. Ive always known I hated a flat in room response however I never fully understood why. I agree, trying to correct anything above 500hz just doesnt sound right.
Excellent explanation. When you mention about build up and reflection of bass and high frequencies because of room acoutics, do additional speakers in the room ex. multiple subwoofers or multiple speakers increase the build up? Or change the dynamics of the room?
I still don't really understand why a speaker that measures flat in my room is sounding anemic. I mean it shouldn't really matter why they measure flat as long as they do so, right?
Great video. Leaving reflections out for the moment, would it be valid to imagine a direct bass wave falling off quickly on its way to the listening position while a direct treble wave falls off less quickly because a greater proportion of its energy output is directed at the listener? If so, I think that would be a good argument for a bass horn with a large mouth to make the bass more directional. Or alternately a huge woofer or woofer array.
Yes there definitely is, but in a room its a little more complicated than that since much of the bass propagates modally. It doesn't so much fall off faster per se, but rather the speaker is just providing acoustic excitation to the room since the space is quite small, whereupon the various modes determine how it propagates to the listening position, with the usual peaks and nulls that occur. The usual ways to handle optimization are to either run two subwoofers which allows you to optimize how the room modes are excited, or by running a speaker with a cardioid pattern which will lessen how much the speaker interacts with the portion of the room that is to the sides and rear. An example would be the Kii Audio Three speakers, which maintain controlled directivity down to about 100 Hz. This means that even below the transition frequency of the room the listening window is still maintained to a degree as well, which can aid in how the speakers image. In keeping with the video's theme, the caveat to this is that you will need to have a good idea of what the speakers radiation pattern is before attempting EQ. With something like the Kii Three, the usual "-1 dB/Octave" in-room response wont really apply. For the most part, it will indeed measure (or should measure) pretty flat in-room due to its very good directivity control. The good news is that you won't have to do much besides nock down some of the bass modes to clean it up since its response is very good to begin with. The really bad news is that speakers like this are usually stupidly expensive. They would set you back something like $14k USD. Better might be to just buy an extra sub to help optimize the room instead 😉
You just blew my mind. So is there a specific in-room slope/curve that is ideal? In other words: if a speaker has a perfectly flat on-axis anechoic response, is there a corresponding on-axis in-room response?
It depends on the radiation pattern. Basically, how wide or narrow the speaker radiate sound toward the front. The more narrow the radiation, the less reflections and the steeper the in room slope.
Bravo!!! Thank you for this discussion, which is super important. You do a GREAT job of teaching the concepts, as well as providing the examples of how bass and treble interact with our walls. I hope everyone who doesn't have the technical background watches this before they drop any money on speakers.
Great stuff, Erin. I'd love to see you do more videos on in room response and how to manipulate it using speaker placement. Luckily nulls typically occur at bass frequencies so subwoofer placement can help break up the room modes that form at those frequencies. Instead of have a single radiator or a set of radiators (two tower speakers) at one end of the room, you can spread the radiators out within the room and this is what helps break up the low frequency room modes. This is why multiple subs are sometimes used. This is what seems to work pretty well for me: I have a null at 100 Hz. When I only had tower speakers it was very noticeable. The tower speakers are at one end of the room, a few feet from the wall and the listening position is on the couch at the other end of the room, a few feet off the back wall. These positions are not ideal, but this is the real world. In order to help reproduce low frequencies better and to help break up room modes I bought a sub. In my 2.1 setup the tower speakers are still in front of me, but the sub is on the left side wall about 1/4 of the room length from the rear wall. I set my crossover frequency to 100 Hz (the -3dB point of the filter). At 100 Hz half of the signal amplitude goes to the towers and half to the sub so the same modes that would occur if I only had towers are broken up a bit by the sub because all three speakers are interacting at 100 Hz. If I move the sub forward and back along the side wall I am pretty sure I could tune the speaker system and the room to reduce the null, but in the real world there are constraints like the position of my fireplace and my wife's aesthetic preferences. Adding a second sub could also help, but I think my next investment is going to be a DSP like the miniDSP Flex. This will help tame some non-linearities I have in the frequency response of my system. My AVR has a limited equalizer and I can't set the frequencies or the Q of the filters. I don't really notice the null any more.
Some other TH-cam channels (won't mention any names) show in room measurements of the speaker they are reviewing and talk about how "flat" it is and don't mention anything about this. I just shake my head...
Yup. My NAD includes Dirac Live below 200Hz. If you set it up and leave it “flat”, it sounds awful. Dirac experts recommend boosting the bass by about 6dB and saving it as “normal” for this very reason. “Flat” would be +3dB. My Yamaha stereo receiver uses YPAO and I use its loudness compensation with no reservations. I also boost the bass by about 2dB. “Audiophiles” are nuts. They will buy a preamp or amp with no EQ option and then try speaker after speaker until it sounds right. Huzzah for tone controls and room EQ!
I recently made a TH-cam short about flat response in-room vs anechoic and asked if anyone wanted me to expand on the topic in a future video. The response was pretty positive so here we are. I hope you find this informative.
I also hope the next time you see someone make the same mistake of thinking they’re the same thing that you can use this video to help them understand why they are not.
It’s not just people on forums. I’ve seen many audio influencers/reviewers show this same misunderstanding.
There are many caveats to a topic like this, but those caveats are a rare exception. This video is not intended to be a deep dive into the caveats and certainly not intended to make the statement that my discussion is always the case. It is intended to be a 30,000 foot view of the topic.
If desired, I can create future videos which will dive into the topic a bit further. For now, this is the jumping off point.
You mean videos WAY off the mark that drive me nuts like this one?
th-cam.com/video/r1IhzuGDkkA/w-d-xo.html
Your video is logic and reasoning to my ears. Pun intended. Literally scientific. That other video drove me nuts.
Thanks , so so much for all you do Erin
I knew there had to be a reason that I hated the sound after I did an Audessey EQ. I immediately disabled Audessey.
I also had the problem with my speakers and I figured out, that simply listening to a slow frequency sweep and properly equalizing the percieved loudness of all frequencies for each channel individually gave me the best sound quality and clarity. Tried 'flattening' out the response via a meassurement mic and while the mic said that it was good, everything just sounded awful to my ears.
@dreieinhalbeck1528 I guess that's the perfect way to do it. I'd assume the mic is the perfect way to make it all "flat" or be able to tune it to your profile. The thing is, we listen to the end result with our ears, which are either not perfect or we may not actually like that "perfect" sound.
@@danielh12345 watch this:
m.th-cam.com/video/zrpUDuUtxPM/w-d-xo.html
I knew a lot of these concepts from doing research and watching videos over the years. But this is the best and most concise explanations of all of these concepts that I have ever seen/heard.
Wow! Thanks for that!
Odd that it hasn't been elaborated on as much as each speaker will have its own unique in-room response based on its dispersion pattern, and that really underlines why measurements are essential. You have to have some idea of where it makes the transition to the listening window before applying EQ, especially when subs are involved. Need to know where they need to intersect the main part of the response in order to blend in properly. Being a nearfield user, I had to work this out myself years ago when setting up systems since its much easier to use measurements to build up what the in-room response needs to look like for larger speakers rather than just doing it by ear. If I recall Sean Olive had the rather bland comment of "its because the sound is comprised of both direct sound and reflections" on ASR which wasn't too insightful.
Excellent video. I like how you explain objective data and how it correlates to what we hear. Hope to see follow up videos to this.
Thanks, will do!
Thanks a lot, sometimes when I watching guys like you I regret not working in the field of acoustics, this world is really exciting!
Excellent explanation of what I have been preaching for decades. Thank you.
You could also add more on room absorption.
Wonderful video.
You explain things perfectly for me. I had so much information already in my head but didn't really see the full picture, until now. Thank you Erin, much appreciated 😁👍
Great explanation of room response. I recall when taking speakers outside for a party and the bass response was so thin. I can see why pro audio uses many large bass cabinets and a lot of power.
That’s a good point as well.
Thanks for the video. Most folks need this education.
0:05 "Flat anechoic is not flat in-room response".
"You basically put a speaker into a container."
Unfortunately, some containers (rooms) are better than others.
5:06 Shocking what happens once you put a speaker into any room.
7:53 so you typically get enhanced bass and tapering treble?
10:24 The speaker dominates the sound above 400 - 500 Hz.
Below that the room dominates the sound.
Thanks for making this video after that short!
Good stuff, Erin, and a subject that greatly needed to be addressed.
Great job ! I have seen several of your videos and have decided to subscribe. I am glad that you are bringing some science to this otherwise subjective field. Too many vendors out there selling products that exploit the uninformed consumers
I take Erin's advice, and it always helps me with my room sound. Much appreciated 👍
What about near field response? For example, various near field speakers that measure flat on axis will measure almost completely flat in a room measurement taken at 1m distance.
Yeah, nearfield is a different universe. But anybody away from the LP will have a very suboptimal experience. ;-)
Great explanation, and I love what you’ve been doing for audio enthusiasts.
I would only say what I also believe to be correlated with what Dr. Floyd Toole called “the circle of confusion”.
In theory, if all recordings started (many decades ago) with speakers/monitors that measured flat in room, all the mixing, EQ and even microphone placement/response would have to be tailored to sound good with that response.
But that’s not how it started, and it would be a lot harder on the earlier recording equipments to deal with that added bass (that would be necessary to sound good and balanced with a flat in-room response.
In any case, it’s too late to change how it all started so many decades ago, and making a loudspeaker to sound flat on most rooms (and even studios) would be a moving target, and the anechoic measurements should be more consistent.
That being said, it’s still a moving target, as most recordings were made on very unique playback systems (mainly loudspeakers and studio acoustics), and most well known studio monitor manufacturers were clear on measuring how much different the same monitor model sounded on different studios (that is often the base for advertising how much their room correction features will help on trying to level things out, but the fact remains).
It’s also not uncommon for loudspeakers that are considered a “reference” on some studios (like Abbey Road and B&W 800) failing to be flat even in anechoic measurements (even in the mid/high frequencies), which doesn’t stop them for being widely used for mastering.
The same can be said about the famous “BBC dip” deliberate response, that we can agree or disagree to be a good or bad thing, but it would be hard to ignore that we’re the reference used to mix many recordings over decades.
IMHO, an anechoic flat speaker with controles off-axis response does have the _potential_ of sounding best with different recordings, but not necessarily with all of them, and this goes back to the “circle of confusion”…!
If a mastering engineer used monitors with the “BBC dip” in the most sensitive audio range for vocals and “presence”, either he was able to compensate for it with the accumulated experience (which definitely was the case for some of the greatest), or playing it back on a flatter loudspeaker response in the range would end up like a “BBC peak”. 🙂
Most subjective audio reviewers used a wide range of recordings to “evaluate” loudspeakers, often introducing even more inconsistencies (how can you compare two loudspeakers with two different recordings?).
But even if any reviewer chooses to listen the same predefined tracks for loudspeaker evaluation, the question still remains:
- Why does he/she use those particular tracks, and not others, that would sound worse on flatter anechoic loudspeakers (but maybe better with less balanced speakers, maybe closer to the ones that the record was mixed/mastered with? 😉
I’ve been in the audio business for some decades now, and I made several audio demos, and was the listener of many others.
Making any good audio demo implies taking the time to try what tracks make the loudspeaker shine, and a particular loudspeaker will usually have some specific tracks in order to accomplish it (sometimes it can change depending on the room’s acoustics).
While that may seem like a biased way of making a demo (and it certainly is in some ways), what happens if the prospective buyer happens to listen that kind of music and recordings?
There are certainly very audible cues on music genres (hard-rock or heavy metal tend to have less bass than jazz or hip-hop, pop vocals are mixed in a different way on every decade, etc), which makes a challenge for any loudspeaker (or headphones) to sound great across such a wide range of sonic signatures in the recording itself.
This is one of the reasons that makes me believe that removing even the most basic tone controls on amplifiers was far from smart, with audiophiles believing that they would be closer to the original recording by avoiding the circuit (and ignoring how much “EQ” any loudspeaker and room will end up introducing on the sound that reach their ears)!
Maybe that’s the reason why loudspeakers always fascinated me the most on any audio playback system, since they all end up introducing their own sound signature, and while some recordings may sound their best with a particular loudspeaker, other recordings will sound best with a different loudspeaker (within reasonably well behaved loudspeakers).
Let me reinforce how much I value objective data, and trying to understand the correlation between measurements and what I can hear.
I’d say that actual anechoic measurements are the only reference point that doesn’t change, since once we put the loudspeaker in a a room, it can work with or against it, and no reviewer is going to listen to a loudspeaker inside an anechoic chamber for a subjective review (and it would be worthless if they did).
But in the end, and like you said, measurements are useful for making some baseline comparisons that may be helpful at selecting an comparing loudspeakers, but we still need to listen to them in our rooms, and with the music that we consider as good reference points for the music we listen the most.
In the end, finding the “right” loudspeaker for us (and the our room) is still a moving target for several reasons, and until now, the best compromise that I could get is to have more than one system (with different loudspeakers) around the house, because some records make me want more rolled of highs (it sounds more “comfortable” on longer listening sessions, while other records will sound more exciting and interesting with more highs (giving them a sense of a lot more detail).
Measurements are the only objective way of comparing loudspeakers against a fixed reference, and that’s huge.
S
But loudspeakers are simultaneously the less complex equipment on most audio playback chain (from an electronics perspective), but also the most complex “device” to make it work with every room and musical preferences.
There are so many different amplifiers that sound pretty much identical, but it’s virtually impossible to make to different loudspeaker designs that sound nearly as identical between them.
And I’m not sure that it is ever going to change, just like the same orchestra will never sound same on different concert halls. 🙂
I don’t have nearly the same passion for amplifiers (let alone dacs), probably because if an amplifier or dac makes such a significant difference as two different loudspeakers, one of the amplifiers need to have a terrible design or fault (aside from power, if we push them outside their limits).
I love these kinds of educational videos, keep em coming
Ok so flat response is the target curve of the speakers themselves (measured in an anechoic room), but then, what is the target frequency response of a room? You say it that curve would have the bass elevated and the highs decreased, but is there a target curve that exists in all studio rooms that we can try to get close to, precisely measured?
Great question. I know this is covered in Floyd Toole's Sound Reproduction. There is no rigid target curve because studios and domestic spaces will always vary. The idea is to have absorption/scattering evenly across the hearing spectrum (diffusion isn't possible in such small spaces), fix room nodes etc. An anechoically flat loudspeaker always translates well in such a listening space, and roughly speaking, the target response will gradually slope down from the bass frequencies toward high frequencies. Takeaway is to buy an anechoically flat loudspeaker, set it up well, and don't use room correction software to flatten the response, except for a couple of room node low frequency peaks.
harman target, maybe?
@AvithOrtega
the curves aim for 'natural' not 'studio' sound when it comes to speakers and headphones.
there is no such thing as precise 'studio sound' just like there isn't one for 'concert hall'. each studio and each concert hall have different characteristics (less variation for studios of course).
in studios the important thing is familiarity (according to sound engineers). w/ enough experience/familiarity sound engineers can predict what the audience will experience and they try to match that to what the artists intended.. their tools are aimed to help them detect potential issues not necessarily to make an enjoyable listening experience.
sound engineers often use monitors or presets that help them 'magnify' fq ranges they consider need extra attention, much like using a magnifying glass. as such, 'studio sound' is not as pleasant as ppl like to imagine. same goes for recording rooms with the most drastic being the 'booth' for voice recording. in such 'quiet rooms' the sound is truly unpleasant as it deviates a lot from our day to day experiences of hearing noises and sound reflections.
ps: as @shalinkochar1081 mentioned, for all intended purposes, we the listeners will never hear the finished recording the engineers/artists heard when they decided it is ready for release, regardless of the room and sound system we use. a great sound engineer once said 'if one wants to hear in high fidelity a recording of a live concert they need to listen to it outside on an identical PA system and if they want to listen to a studio recording they need to build a room identical to the studio and use the same equipment'.
@@shalinkochar1081 The problem with Floyd Toole and Sean Olives approach is; for the most part they're not targeting audiophiles, they're targeting consumers. That's the success of the like of Bose and Harman group. They may have the odd product for the audiophile, but in most cases it's boom boxes, decidedly average car audio products, but they're targeting people with average income, that want to have a bit of sound in the kitchen maybe, and they want to pretend that their equipment is good, enter quoted high wattage numbers, flashing lights etc.
I take Floyd Tootle's approach in the realms of what he was paid to do, rather than a ROT!
Looking clean and fresh my man. There are definitely speakers we should avoid. The room and speaker combination matters.
It should be noted that this happens to live instruments in any given room too, which is why in-room response is what humans expect to hear. This is also why I enjoy near-field recordings over concert recordings, so I'm not "doubling up" on the room ambience.
Great information 🎉 Keep expanding on it, thanks
That's the best I've ever had soundwaves explain to me what's going on in a room it's and it's really helped me a bunch thank you
Great to hear!
Great explanation! The visual representation made it easier to understand. Deserves more subs, for sure.
Wow! Very good informative video. You explained it in a way that even a child would understand. I now understand why Audioholics recommends the 500 hz room correction. Looking forward to more videos like this on some of the technical side of home audio. 👍🏽
Glad it was helpful!
Great video, glad you're back. I bought the IN-5 thanks in part to your reviews!
I'd love a video where you'd explain how to do proper room eq (and what not to do).
Thanks for the videos.
This was a really great video, I learned a bunch. Thank you for making this!
Thanks!
Thank you!
Very good video Erin. Thank you. 😊
Great video!
Super explanation, Erin. You could probably do a part two regarding absorption in typical listening environments which make this anechoic to in room difference even bigger. And for good measure what it takes for anyone trying to manipulate/improve acoustics in the bass....
Yes I would love if you made a part 2 explaining sound absorption and how it works. Also, if audyssey, YPAO etc with sound absorption is better or turning audyssey, YPAO etc off with sound absorption is still better .
There’s a great you toober on acoustics. Yesco. German guy.. sorry I cannot think of exact Chanel name. Even then it’s pretty nebulous feeling how to treat fir lower frequencies.
@@chinmeysway He's good. He writes his name Jesco, and the name of his channel is Acoustics insider. He does, however focus on studio design, rather than home audio, and for the most part on nearfield listening. If you go his way, you will arrive at a very dry representation, very fra from what Erin would prefer. But yes, Jesco appears to be very competent. And I believe that he'll have a bunch of things to teach even to those preferring a more wet/reverberant reproduction.
Great video! Thank you for making this.
What a great explanation! I tried explaining this on another channels comment section. You did a much better job! Btw your objective scientific approach is very much needed, I wish you as much success as possible you deserve it. The work you put in is much more valuable than the sea of subjective feelings they have about audio equipment.
Science should be objective, theories are subjective until proven.
Awesome, thank you!
Hi Erin, can you please elaborate on WHY measured-flat in the room is bad? I'm guessing if you measure a linear monitor at near field, it'll be flat. What's wrong with correcting room effects that cause a downward slope in response? (and that's not limited to 500Hz btw)
@erinsaudiocorner this was the topic of our group chat last night. We need your input on this matter!
Imagine your voice. We can say that you have a flat response of yourself (you sound exactly like you :) ). Now imagine you are being recorded in a studio with no room sound. Now lets move to a living room with typical room sound. If you start speaking, one can hear you and the room. This is considered your real voice, since you never speak with people in an anechoic room or a studio, so this is considered you. Now lets take the recording, which is you minus a room. If you play it on an anechoic flat speaker, then its: (you - room) + room = you. If you play it on an in-room flat speaker, its (you - room) + room - room = you - room, which is you sounding like a tin man.
@@okosakaroklenni A few questions:
1. Why is it ok to correct what the room does at lower freq but not at higher freq?
2. You're effectively saying listening with near-field linear monitors, or accurate headphones, makes you a tin man since a room doesn't modify the sound. I dunno about that.
3. Every room is different, and by not correcting its effect you won't hear the intended tone balance. Isn't the masterer using linear near field monitors?
@@f7i6f67fkh
1. You want to correct what the room does at HF. Its not about frequency response, but an even reverb time, so you don't f*ck up power response. FR is not really affected by the room. I mean it's too chaotic, you don't really hear the comb filtering.
2. About headphones... I had a very linear headphone, and hated the sound of it. you can get used to it, but don't really want to. Except of course if it is your thing. Near field monitors still have the room sound, you only get rid of early reflections. But SBIR from the walls and especially from the desk is a real problem.
3. The sound engineer is mastering for a target "audience". And you don't really want to listen to music on a gear like that.
+1: completely EQ-ing out the room to a flat response is not the same as treating the detrimental effects of the room like long RT, giant 20dB canellations and early reflections. And it's not the same for a studio, where you need a standardized sound for professional work, and a listening environment, where good psychoacoustics is important. At least this is what I think, as I'm not a professional, just read a bunch so that I could treat my room. Also this is what a professional engineer told me when measured my gear. He told me I want the speaker linear anechoic, and then add an even room sound.
@@f7i6f67fkh
1. acoustic room treatment covers a wide range of fq. for higher fq a combination of absorption and refraction/scattering is used. as the fq decreases it becomes more and more difficult to absorb and impossible to scatter (redirect) and that's where the shape of the room is designed in such a way to minimize 'room modes'. in short the ratio of LWH and angles play the largest part.
for professional purposes, rooms are designed/treated for a rather low reflection* index not for 'sound quality' but for analytical reasons (so the engineers have an easier time detecting what does what). w/ that in mind, it is often the case before a mix is finalized and sent to mastering, the recording is auditioned in other environments outside the studio in an effort to check if the intended tonality/vibe/etc of the recording is maintained for as many possible listeners as possible (some listeners will listen/enjoy the recording in their cars, kitchens, livingrooms, etc)
*they do not aim for 'zero reflections' because such a room is fatiguing. being so different than real world audio experiences our brains have to work overtime trying to understand the surroundings as there are no reflection cues to analyze (can't tell the size of the room, our position in the room, etc). as the brain works in the background extra hard, sooner than later the listener will feel exhausted or even stressed..
2. all those devices account for our preferences, a response that seems natural to us. headphones have an inbuilt fq response that is rather chaotic but based on studies produce a balanced/pleasant sound. same applies to studio monitors. in fact most of them have settings (some models jumpers or switches to "EQ" their fq curves based on the environment they're used in and some offer those presets in their menu). that being said, those devices are aimed to help engineers detect easier/faster issues w/ the recording, mix or master. their purpose is not necessarily to sound natural. for that reason many engineers develop a workflow that involves checking their work using different sound sources. the ultimate goal (and it's an impossible task) is to make such a recording that sounds like the artists intends to every listener. a good engineer is one that understand what the artist intends and is able to shape the sound is such a way that a listener in their car will get the same 'vibe' as one who listens to the recording in their bedroom. as you can imagine lots of compromises and tricks need to be deployed for that..
3. when mastering, just like when mixing, the sound engineer checks for issues. that's where the main efforts are concentrated. next is obtaining a vibe that's as close to the intended vibe requested by the recording artist. finally, they try to shape the sound in such a way that it will maintain some of that vibe over a wide range of listening environments and devices. many engineers say 'linearity' is not as important to them as 'familiarity'. that means they choose tools that offer them the best chance of predicting what the recording will sound like for the vast majority of listeners and because none of us hear the same things (in fact out hearing changes w/ age, time of the day, mood, etc) sound engineers prefer tools that work best for them (hence not all studios use the same monitors, say the 'best' monitor available at the time even though some could afford any available monitors). monitors offer presets that change the character of the sound, some deploy very drastic changes such as making a 4way monitor only play two of the transducers in a 'full range' manner. this shows how much effort is put in trying to make 'everyone happy'. in effect they are trying to 'guess' how the recording will sound for ppl... the more experienced an engineer is, the better their 'guess'. real good ones can not only make that 'guess' but also have a feel for what a certain audience target prefers. it starts w/ the recording engineer and end w/ the mastering one...
in a 'perfect world' there would be multiple mastered releases for the same recording. one for listening outside on the pool speakers, one for headphones, one for powerful home theaters, you get the idea. but that's impractical. so in reality regardless of the room and sound system, we won't ever hear what the artist heard when they decided the work is ready for release...
Our ears and brain also account for floor bounce, and trying to EQ that out also makes speakers sound thin.
Great explanation.
Thanks Erin!
My lightly "treated" music room had massive bass modes at 27 & 54hz. A DSPeaker Antimode preamp eq'd them to flat.
The result sounded pretty anemic, so the instructions recommend raising the bass level afterward. Better....
Currently not using any eq with (dipole) Maggie/REL and occasionally Rega TL speakers.
You learn the sound of your room. But make it as comfortable as possible before you add speakers and music:-)
Always great explanations. Thank you
Thanks Erin.. Only been watching for month or so.. I've learned so much. You have a great way of explaining things in my opinion..I understand and realise I'd like to learn alot more.. My budget is more a diy build.. My sound space/living room/kitchen Annex is relatively small. And long. I'm aiming to build a great home theatre.. /hi fi stereo.. My listening is about 50/50.keep hearing that I have to make better half happy while still treating the very reflective room.. Love your vids... Thanks..
I'm so glad!
Thanks for this great video & all the work you do / all the data you share👍
My pleasure!
Excellent, more of this please.
Thank you Erin for these excellent educational videos. Keep up the good work.
Thank you Erin! 🎉 I understand now 🧠
Excellent!
Great Video Erin!!! These are the types of videos that Make it All make Sense. I love these, Even and Old Dog like me can learn something, Keep up the Great Work!!
Glad it was helpful!
Great explanation Erin. I’d very much like it if you were to get together with Danny Richie and give feedback on his system and what he does, as Jay of Jay’s Iyagi and Chris from Vinyl Attack have done. I find your videos very informative and find they complement what I’m learning from Danny’s videos very well.
Also needed is survey of how companies test for sensitivity rating: is it in a room/ room size, is it outside, is it anechoic, do they round up to much regarding room gain etc etc
You are by far number 1!
Succinct explanation. Thanks Erin!
Great video! Thanks!
In the early 90s, I graduated college and bought my first speakers. I bought a pair of Infinity Advents, because they were the “flattest” speakers I could afford, per an article in Consumer Reports. Despite being “flat”, I turned the treble up a little, and I turned the bass down a little. As I learn more about room acoustics, I’m wondering if that might be because some of the highs get lost in the furniture and some of the lows gain from the walls. With that in mind, I’m also wondering if it doesn’t make sense to look for speakers with a little bump in the highs and a little roll-off in the lows.
Damn I love your work. Great video my friend
Thank you.
Thanks for the explanation, that was really informative and helpful
Glad it was helpful!
Flat response is in relation to input signal at x dB across entire frequency spectrum.
The music we play it’s not linear so we won’t hear flat sound because you have calibrated speaker to have flat response in your room - for specific sound level. True under 500 is critical where the room dictates the sound but it doesn’t mean if you calibrate rest of the spectrum, then it will sound dull. It can correct unwanted peaks, fill in small dips. DL does it well, Audessey has tendency of sucking life out of sound because it does a poor job at determining room interaction and applying correct filter.
Excelente video 👍
Now you've said it all. The various speakers I've had in my room always measure more or less the same in my room. Instead of spending money on speakers, spend it on the room.
Great video! 🍻
Thanks! 👍
So, my last post referred mainly to high fidelity, 2 channel rooms...whic is hard enough to treat to flat response.
Most here are HT/AV, but with so much more LF and with multiple speakers, a flat room EQ is even more challenging, and more expensive, and theaters are usually small rooms, less than 30 x 20.
However, the same general methodology applies as in higher end 2 channel listening rooms.
Thank you.
You're welcome!
I like this kind of videos, where you dive into the matter!
One remark. You said that with an omnidirectional speaker the anechoic response and the in room response are the same. In my opinion omnidirectional speakers don’t exist. The speakers that claim to be omnidirectional are only “omni” in the horizontal surface, not in every (omni!) direction!
Good thing that most decent amps has bass and treble controls. Now you know what they are for. We knew this in the 1960s, then everyone forgot what good equipment can do and sound like. In the last two decades, designers spent less money on the R&D electronics and more money on the aesthetics with gold plates sockets and included as much weight as they can to give the appearance to be better and sleeker and of course much more expensive. Those days, I remember a top system (as described in Hi-Fi News) Includes a turn table, Like Linn Sondek, Thorens Rega, Pink Triangle, top-end cartage, like Kutsu Black, Dynavector Carat Ruby. Lin ASAK, Shure V15, etc. excellent tone arm such as the SME, Linn Itok, set of three-way floor standing speakers'such as the KEF, Rogers, Spendor, B&W, Cellestion, Richard Allen, etc, the best amplifier money could buy, including makes such as Pioneer, Sansui, Sugden, NIAM. Kenwood, McIntosch, Marantz, Luxman, etc. all for the mighty sum of 1000 British Pounds. Now is a good time to donate that new amp, micro sized 4 inch speakers, streamer and DAC that you bought to the salvation army and get yourself something vintage from the 70's or early 80s and really start to enjoy what we had access to in the days past. Nowadays, you get a single knob, including a plastic remote control, pint sized speakers and power bricks, all sounding like crap but costs more than a half decent house, only to be compelled to upgrade each for something with a smaller driver, bigger knob or LCD each time a neighbour buys something more expensive.
A good video, as always. However, it would have been nice to see an example of what you consider a good in-room response for a set of speakers.
This is awesome. This is useful.
Glad to hear that!
I wish the recording labels released their recordings with a variety of differently mastered equalization options to choose from. That way, we could select a version of any particular recording that best suited our HiFi system and room response, without needing to adjust our system settings (distorting the frequencies), to get closer to a true flat response result. Even a choice of 3 different versions would be helpful.
Thanks. Very helpful. It’s always a bit challenging for non techie home audiophiles like me to sort out home audio acoustic treatments and EQing. A lot of trial and error and frustration. But it is so satisfying on those not so often occasions when I do finally get it right. Or do my ears tell me.
If your ears don't enjoy what you hear, then no matter what "acoustic treatment"or EQ you apply, or whether your system is hyper expensive, you have actually wasted your money. 🤥🤥
@@nicoras8803 so the question is do we trust our ears or can our ears be trained to listen better?
Not sure why you don't have more subscribers....excellent videos.
Great video! Makes total sense, big a-ha moment here.
Glad it was helpful!
Great video for us non-experts, would love more videos like this
Great stuff, best way I've ever seen it explained, should really be useful for people new to the hobby.
I think that is where Erin really shines. He can explain things to the lay person in a way they can understand. I like to watch Amir as well, but I have an engineering degree. His explanations can get a bit technical.
Bro I cant remember what video of yours I watched where you showed a phone app to record your speakers to see the frequency graph?
Budget Stereo Systems You Will Love
th-cam.com/video/6GcFznDiJQU/w-d-xo.html
@@ErinsAudioCorner Thank you
Is measuring with sine sweeps the same response as measuring using the MMM with periodic pink noise?
Reducing the peaks and leaving the dips alone is a good advice : the peaks can be anything (even not speaker, it can be something vibrating in the room) I got my best results by just putting pink noise, and insuring I get the bottom note around 85db, then I eq the peaks down and insure I have a nice slope to 16-20 khz, usually there I am between 77 and 80 db (on tweeter axis V pointed at the mic) . So the fight is more with room modes and objects and glass and eventually some issues with the speakers, but mostly room. And to do the eq well you need everything playiong : both speakers and the sub. Because eq changes if you cut any of them. Eq changes also if you move the crossover. Eq then and get a dip or a peak elsewhere. That's a living room, not a lab.
This makes alot of sense... my dad is having an issue with low frequencies in his room (it's a dedicated room) he was told he should deaden the room with panels and pictures on the walls... is it possible the room is too dead and that's why there's an issue with thin sounding bass? Speakers are KEF R11 towers with (2) 12" subwoofers The room is 15X18
I was thinking this the other way, our ears are less sensitive to low frequencies and more sensitive to high frequencies, our ears are no professional microphones
Excellent video Erin!! Keep up the good work!
Thank you so much!!
Erin - I have to say this is the best video of yours that I have seen! Excellent coverage of a complex subject. I wish you might have added a *bit* more about *why* drivers become directional - as the wavelength gets shorter and shorter, and approaches the width of the driver - it becomes more and more directional. I.E. it gets narrower the higher the frequency; and becomes a "beam" when the wavelength is smaller than the driver.
I like the ripple tank illustration. As complex as it is - a room is obviously 3D - and so the wave patterns are *even more complex*.
I did and I had graphs. But I edited that out because I really wanted to keep this at a high level. I know if I get into the weeds then that may push the casual watcher away. My main point is for the viewer to understand that flat isn’t always flat. I’ll likely make some follow up videos to this, though, and will talk about those aspects, referencing this video as the jump-off point.
@@ErinsAudioCorner please do.
@@ErinsAudioCorner Neil Blanchard , you should send him your speaker that you have designed. Would love to see what the Klipple says.
Great video
Thanks!
GREAT explanation ! Erin you are the man !
Nice explanation Erin. It reminds me of a time when I first bought my new shiny RTA and I set out to force my sound system in the trusty Escape (using high-end Morel separates, DSP, Rockford Subs, tons of sound deadening...anyway, done right...not a wing it on a weekend install by any means). I was so excited when I had that response looking like the "JBL reference curve" with the gradual downward response toward the high end. I rushed to get in to listen and it sounded hideous. I mean, it sounded worse than having all DSP settings flat and just letting it do it's thing. What I learned made the most sense was to only cut peaks and limit boosts to 2 dB. Anything that boosted screamed "HERE I AM" when you sat in the car. Anything cut was "out os earshot, out of mind". I could never resolve that pesky midbass cancellation issue because standing waves don't respond to boost or cut but that's my story. Your explanation is a concise version of a very hard lesson it took me a while to learn.
Great video! Dumb question: Is the front wall behind me or behind the speakers? I think different reviewers might be referring to the front wall as the wall directly behind the speakers. Ex."I set up the speakers pulled out 3 feet from the front wall.", while review measurements refer to front/rear wall reflections. THANKS!
It’s super confusing, I know.
So..
In the SPINORAMA data the reference is the speaker. So “front wall” is the wall in front of the speaker. Which winds up being the wall behind the listener.
For my sake, I wish it wasn’t labeled the way it is but I understand why. It’s just awkward to talk about the speakers front/rear wall vs the listener’s. 😂
So I understand that direct sound being flat above transition frequency is most important.
The angle comes from early reflections and sound power, not direct sound being altered?
So, is it right to say that use of acoustic panels and bass traps is useful in that they address stacking of LF, but one needs to be wary of EQ-ing the sound to get a flat in-room response?
I have an old (1982) set of JBL L96 speakers that sound exceptional in every room I've had them in over the past 41 years.
If anyone here mixes / masters tracks I'd be keen to know what curve is targeted in studios. Is there a standard for this, or is it down to the preference of whoever mixes the track?
I always assumed a flat curve within a couple of dB was the goal, so tracks would be mixed to sound best with a flat response. Perhaps a realistic but still smooth in room response is targeted, to be representative of a typical "decent speaker" in a typical room.
To add a layer of confusion, 90% of songs will either be listened to on airpods or in the car with additional signal compression applied over the radio. Must be a heck of a job to choose how to mix a track to sound decent in the most scenarios.
What if the measured response is sloping upward (no EQ)? Does that mean the response is nearfield dominant? Would you EQ the treble down at that point?
I learn more from your videos than I’ve read in the past 50 years. Speakers that are expensive and have boosted highs and lows then get rave reviews just confuse me. I prefer a flat anechoic response. Then fight with the room.
Thank you for your awesome video. How much roll off or taper (in dB) should a great speaker produce when you do an FIR graph with REW? If an FIR graph shows the speakers are too bright can you use EQ to roll the highs off more? I know you say not to boost the lows, but what if when doing so you get lucky REW is showing a better response curve? In that case is it OK or still never boost the lows? Thank you for your knowledge!
Companies must mostly measure things in non anechoic rooms I’d assume though so it’s all really non conclusive. Any guidance on that would be lovely. Are there any stats on how many companies / which ones measure at all of anechoically?
Excellent video!!! I struggle to explain the same to people - I’m just gonna point them to your video from now on 😊. I was gonna add that maybe it’s worth pointing out that higher frequencies are more easily absorbed (e.g., sofa, carpet, curtains, etc) then low bass, and are less likely to “build-up”/“reflected back” - and thus further contributing to the overall downward in-room response tilt.
Glad it was helpful!
This is the knowledge people need. Great video!
Hi Erin , how do you know when we can equalize a speaker and what are the frequencies that can be adjusted using inclusive parametric equalizer.
As i understand from one of your videos frequencies below 200hz could be adjustable but I think the mid high and high frequencies when you adjust these we can change the tone characteristics of the sound .
When the room correction systems as Dirac an others can be applicable without changing drastically the tonal quality of the recording .
To me we have to start with room treatment that in many cases could solve the problem for mid and high frequencies and use the equalization to correct the room node modes.
The correction room systems works in all the cases or have certain limitations.
I see some reviewers using pro DSP parametric equalizers to solve room problems but this i think does not solve all the problems
Thanks for your response
Thanks so much for your well explained video.
Ive always known I hated a flat in room response however I never fully understood why.
I agree, trying to correct anything above 500hz just doesnt sound right.
Glad it was helpful!
Excellent explanation. When you mention about build up and reflection of bass and high frequencies because of room acoutics, do additional speakers in the room ex. multiple subwoofers or multiple speakers increase the build up? Or change the dynamics of the room?
They do. But whether it’s good or bad depends on placement. Check this out:
www.harman.com/documents/multsubs_0.pdf
I still don't really understand why a speaker that measures flat in my room is sounding anemic. I mean it shouldn't really matter why they measure flat as long as they do so, right?
Maybe your speakers are anemic or your amp is underpowered.
Great video. Leaving reflections out for the moment, would it be valid to imagine a direct bass wave falling off quickly on its way to the listening position while a direct treble wave falls off less quickly because a greater proportion of its energy output is directed at the listener? If so, I think that would be a good argument for a bass horn with a large mouth to make the bass more directional. Or alternately a huge woofer or woofer array.
Yes there definitely is, but in a room its a little more complicated than that since much of the bass propagates modally. It doesn't so much fall off faster per se, but rather the speaker is just providing acoustic excitation to the room since the space is quite small, whereupon the various modes determine how it propagates to the listening position, with the usual peaks and nulls that occur. The usual ways to handle optimization are to either run two subwoofers which allows you to optimize how the room modes are excited, or by running a speaker with a cardioid pattern which will lessen how much the speaker interacts with the portion of the room that is to the sides and rear. An example would be the Kii Audio Three speakers, which maintain controlled directivity down to about 100 Hz. This means that even below the transition frequency of the room the listening window is still maintained to a degree as well, which can aid in how the speakers image.
In keeping with the video's theme, the caveat to this is that you will need to have a good idea of what the speakers radiation pattern is before attempting EQ. With something like the Kii Three, the usual "-1 dB/Octave" in-room response wont really apply. For the most part, it will indeed measure (or should measure) pretty flat in-room due to its very good directivity control. The good news is that you won't have to do much besides nock down some of the bass modes to clean it up since its response is very good to begin with. The really bad news is that speakers like this are usually stupidly expensive. They would set you back something like $14k USD. Better might be to just buy an extra sub to help optimize the room instead 😉
@@mysock351C Thanks for the detailed and well informed response.
Fantastic video! And what about speakers with cardioid directivity?
Thanks! I may try to cover that in a future video.
More like these!
You just blew my mind.
So is there a specific in-room slope/curve that is ideal? In other words: if a speaker has a perfectly flat on-axis anechoic response, is there a corresponding on-axis in-room response?
It depends on the radiation pattern. Basically, how wide or narrow the speaker radiate sound toward the front. The more narrow the radiation, the less reflections and the steeper the in room slope.
@ErinsAudioCorner thanks, I figured that was the case. P.s., the "about me" page on your website says "This video is private"
Bravo!!! Thank you for this discussion, which is super important. You do a GREAT job of teaching the concepts, as well as providing the examples of how bass and treble interact with our walls. I hope everyone who doesn't have the technical background watches this before they drop any money on speakers.
Thanks for the feedback! I really appreciate the kind words. 🙂
Adding delays to your subs helps with nulls sometimes.. is this recommended?
Great stuff, Erin. I'd love to see you do more videos on in room response and how to manipulate it using speaker placement.
Luckily nulls typically occur at bass frequencies so subwoofer placement can help break up the room modes that form at those frequencies. Instead of have a single radiator or a set of radiators (two tower speakers) at one end of the room, you can spread the radiators out within the room and this is what helps break up the low frequency room modes. This is why multiple subs are sometimes used.
This is what seems to work pretty well for me:
I have a null at 100 Hz. When I only had tower speakers it was very noticeable. The tower speakers are at one end of the room, a few feet from the wall and the listening position is on the couch at the other end of the room, a few feet off the back wall. These positions are not ideal, but this is the real world. In order to help reproduce low frequencies better and to help break up room modes I bought a sub.
In my 2.1 setup the tower speakers are still in front of me, but the sub is on the left side wall about 1/4 of the room length from the rear wall. I set my crossover frequency to 100 Hz (the -3dB point of the filter). At 100 Hz half of the signal amplitude goes to the towers and half to the sub so the same modes that would occur if I only had towers are broken up a bit by the sub because all three speakers are interacting at 100 Hz.
If I move the sub forward and back along the side wall I am pretty sure I could tune the speaker system and the room to reduce the null, but in the real world there are constraints like the position of my fireplace and my wife's aesthetic preferences. Adding a second sub could also help, but I think my next investment is going to be a DSP like the miniDSP Flex. This will help tame some non-linearities I have in the frequency response of my system. My AVR has a limited equalizer and I can't set the frequencies or the Q of the filters.
I don't really notice the null any more.
Thank you. This is something I needed to hear.
Glad it was helpful!
Some other TH-cam channels (won't mention any names) show in room measurements of the speaker they are reviewing and talk about how "flat" it is and don't mention anything about this. I just shake my head...
Use this video to help inform them of their misunderstanding. Hopefully they’ll take time to digest it.
Yup. My NAD includes Dirac Live below 200Hz. If you set it up and leave it “flat”, it sounds awful. Dirac experts recommend boosting the bass by about 6dB and saving it as “normal” for this very reason. “Flat” would be +3dB.
My Yamaha stereo receiver uses YPAO and I use its loudness compensation with no reservations. I also boost the bass by about 2dB.
“Audiophiles” are nuts. They will buy a preamp or amp with no EQ option and then try speaker after speaker until it sounds right. Huzzah for tone controls and room EQ!
Hey, Erin. Great video. I always see the people in videos saying that we want a downward sloping FR, but I've never seen anyone explain why.
Awesome!