I've literally been struggling to determine how to pick what speakers would work in a sealed enclosure and this was the best guide I could find anywhere, thank you so much for this. I'm so glad that I found your channel and I have subscribed and will be perusing your vids to gain all the nuggets of knowledge I can!
Excelent video! Very important information and with a very clear explanation ! Just what I wanted to understand about TS parameters. Now I do understand what the numbers means! Thanks
How do you work backwards? Let’s say you want to upgrade the drivers in your MTM speaker cabinet to better ones. You would measure the inside volume of the cabinet and the port, but then how do you determine which drivers would fit well in that enclosure? Thanks!
The best video on this subject! I got my answer why my calculated volume is coming with a negative sign. Now, what should be done for small speakers with Qts value more than 1.2?
Most likely this kind of speaker will play as a woofer so not much suitable for low freq. Usually high qts means the speaker is stiff and have good excursion control, again its not good for low freq. If it was me ill just make a sealed box to enhance excursion control or a ported box with high tunning like 80hz or whatever is the speaker fs and make it work as midbass, then you should have another speaker for lower freq.
Thanks brother. So it's best to use 3 type of BASS when setting up a sound system ??? Because all 3 type is relevant to the different types of MUSIC u will have to PLAY . !!!!!!!! Don't u think
Hi, Hello, I would like to ask question about right volume of sealed enclosure for speaker DaytonAudio PS95 8 3 1/2" Point Source Full Range Driver 8 Ohm. Every calculator gives me different sugestion about volume, so Im quite confused...Can you give me advise, what is the right size for this speaker? Fs = 119,8 Hz , Qts = 0,72 , Vas = 0,94 l
Ok hello nice to meet you my name is Harold . I have been playing with audio from 8-10 years old . At 47 now every thing has gotten so tech now but I’m enjoy the learning , not to good on mart but as far as experimental yes just to see the out come ! Had a pair of Rockford p1 10” 250rms 500 peak playing with a nippon tubo 12 “bass cannon” the numbers does not match 12s it’s a 1.4 cf tube with a 18” long port at 22 sq inch . I have mounted a 10 half way seald aginst the top ten rear one faced up with the other faced up so isobaric sealed 0.7 between them 0.7 ported then test sound descent not outstanding. But I had a sealed 12” 1.2 cf square box that I turn the tube into it playing now two tens isobaric into a sealed box very big change it really needs just by listening to it the 1.2 ported and behind the 1st 10 then sealed .07 the other 10 then sealed plying into 0.7 kind reverse every thing I got! Of course there was no planning or thinking it was just to see what isobaric does never been close to one before or listen to one on,y pictures on the net ! And I’m not sure if you can or not put isobaric sealed playing into sealed I’ve seen it ported between and to the out in both ways ant together also seen it seald between but never playing into sealed! That brings me to the ? What order is this I’m calculating 4th order isobaric band pass with bad cubic feet numbers it has a good tone and hits decently hard but the low bass is killer accurate I found out one big thing isobaric helps control a lot of distortion that happens even with out the front sealed box I could tell a difference oh I’m running a kenwood in dash kickin-x704 with a audio control epecenter off 110ac converter into a Behringer km750 concert amplifier in a 20x16 8’ wall sealed garage “it’s insulated and plywood all 5 sides setting on 6” concrete” tanks fo all your information I’ve got a skar skv2500 and ax15 sundown audio v2 wanting to build areo port or 4th,6th order for the rear of my Toyota 4Runner I like what you shown here you got my choice down to areo or 6th order I currently have it in a sealed 3.0 box with a 10 k rockvilleRPA16 concert amp it rocks dude it knocks stuff of the cabinet the walls and refidgerator I also run the epecenter on it and half volume I can tell that’s plenty they both perform so well I’ve never had any thing with this much power back to the 4 runner I’m a welder/fabrication expert with Steele descent with wood I’ve placed an extra 220 amp alternator with a belt configuration added a old water pump pulley to my bottom drive off the crankshaft on the motor with 1 battery under my hood 650 can deep cycle marine battery extra volt gauge and light inside for this extra charging system that will have a 750 xs power agm motorcycle battery and a cap I’m thinking 5-10 fard I’ve got breakers and fuses for all of this will have 8” ds18 component set in doors with Rockford punch 200 on tweeters and arc audio 900.1 kar series on the 800watt 8s so I kinda need help with an space that’s 40 inches wide 24 inches long and 24-40 tall. I could go 2x15s if I want to I think they are1500 watt subwoofers what do you think I’m almost there I’m gonna use birch plywood they say it’s stronger and lighter than mdf/particle wood and with 2x15 subs how about never seen face to face isobaric sealed in the middle of the box with two different size ported chambers tune 1 real low like in the 20s and the other side in the 40s that’s what I’m aiming for I’ve even thought about building half of the isobaric loading and have it were latter on I could build the other half and sub then put them together to achieve that isobaric 4th or I guess it could be tuned to 6th order by porting the middle ? Let me know what you think I enjoy this knowledge you share and highly appreciate you for teaching I need to learn more before I can make the judgement of my box problem I have ask for advise from two others on line one no reply the other guy just throws out a basic slot port box I could go on a box building site and do my self the one thing I know for sure I want areo port or ports no matter they are more efficient but the grafts don’t lie you can see the big change in the lines from a slot port to a areo port I have always built seald boxes I’ve just recently got back into this audio game heavy the last year and half and seen all this new to me ports and the technical part of it is way above my head I’m learning slowly I want a good sounding over the broadest band but really low fq bass I think I can get it I know there’s a trade off but I know I don’t want a SPL build we’re it’s only good for 1 fq I’d like to have the range of that 6 th order you did with the 10 “ JL we’re it came in early in the low hz and hung in there to 80 and didn’t drop real bad till after100hz I’m thinking to myself if I hit around 100 hz on my highs decent and 20 to 80 be really killer I’d be plenty happy
Can you do some videos on 6th order bandpass....specifically series tuned 6th order bandpass...and how important is the ratio or what should the ratio be
Thanks for your advice but I love sony home theater sub bass. what type of enclosure they use please explain... And I have TB subwoofer W5-1138SMF can I design box like that
Can you make one video explaining how to apply QE and boost the lower octaves of sealed subwoofer please ... Let's say a sealed subwoofer is rolling off at 30hz, and if we want to push it down to 20hz with EQ, how we can do?? And pros and cons, and limitations etc .
@@AudioJudgement wonderful !! Thanks a lot for reply !! www.diyaudio.com/forums/subwoofers/362350-ts-parameters-decide-eq-driver-handle.html That's a question I asked in a forum and some explanation is given by some nice people. (I'm just sharing for reference)
Hello sir i have eminence alpha 12 american standard series 150 whatts speaker Parameters are as below Qts is 0.77 Vas is 121.5 liters Ebp is 56 Fs is 49 hz So how much quantity of box that is encloser should i do Means lebght and height and widht Calculation formula can you send me sir I hope u will tell me Plz sir plz plz plz I hope u will reply sir
Great video, I am about to finish the DIY T/S test cable you described building in one of your videos (great one) and I can't wait to run some measurements on some drivers I have laying around. In your last video you outlined four factors that need consideration with regards to optimizing box volume to driver Vas, Qts and Fs as well as EBP. As a DIY speaker builder, I would like to know how to determined the optimal box volume, once I have all of the relevant T/S parameters. Let me simplify this further - Once I got real T/S parameters of my driver, I want to plug in the numbers into some online program (preferably free) or formula, and get the optimized box volume according to acoustics suspension or ported design (depending on the driver, of course). Regarding your low subscription numbers - Unless you come up with some viral video, this process takes time and effort. It requires having more on line videos appealing and getting (hooking) people with shared interest. Thanks for your videos and knowledge sharing
What about EBP? Rockford P3D3-10 recommends either sealed or ported. But, winISD Pro and other calculator indicate EBP of 44, thus should run sealed only. So then why would Rockford say and give specs for a ported box design? --I thought that you always run the speaker at double it's resonant Hz or higher. But, no? So, I can design box for ... say... 30 Hz, even though response spec. is not given by Rockford. Or at least I can't find it.
You don't "run the speaker at double its resonant frequency". I've seen stupid guidelines like that before. Like in a 4th order bandpass, the ported chamber needs to be twice as large as the sealed chamber, or some other weird ratio. These are made up "rules". You simply model the frequency response, and if it looks according to your goals, then it's good. It doesn't matter that it doesn't follow some ratio a guy mentioned on a forum 30 years ago. Regarding EBP, yes, it's a way to determine what type of box you should go for. Used in WinISD and also mentioned in the Loudspeaker cookbook. I don't particularly use it though. If I take, for example, a midrange driver, EBP will almost always recommend a ported box (because of higher FS, EBP will most likely be over 100) and people always put midrange speakers in sealed enclosures (in talking about midrange drivers in 3way speakers). It's not black and white. You need to factor multiple parameters when deciding the enclosure type. So, if I want to simplify things, I just like to take a quick glance and Qts and form a rough idea on what enclosure will work best.
@@rogersingh3918 Ya. So, I guess I'm not the only one who picked up on something like that. I ended up going with a JL 10W1v3-2, mainly because it was the easiest in winISD to tune for my RAV4s small real estate problem. But, I had the sub for like 3 weeks. I am just finishing the enclosure. I just don't have time. But, I've seen people in DIYMobileAudio talking crap about P3s, yet when I model them, they seem to perform very well. Any thoughts?
@@RobHTech agreed, I have modelled both 4th and 6th order bandpass using Winisd and Bass box bro 6 and they both have an advantage in output vs regular ported according to RF specs. RF made their subs so they can work on either sealed or ported enclosures, the sub I've got is the RFP punch 3212 and it works great in a ported box, will be louder in 4th or 6th according to the modelling software, have not decided as yet whether 4th or 6th
That's a transmission line. There are pro's and cons to that type of enclosure. Sometimes, that might be just a normal bass reflex with a very long port. There is no benefit for a long port. It's just a necessity to tune a box at a very low frequency
Do back reflections from the back of the box actually cause problems for a speaker driver? Does poly fill really help? I have read only natural wool is useful. What about adding diffraction panels ? B&W nautilus was designed to remove back waves. I have never heard a pair, have any of you?
Depending on which frequencies you want to absorb different materials will work better. You need denser for lower frequencies. And yes, standing waves, if they are bad enough, can cause the enclosure to "ring". Adding diffraction panels can help also. And no, I haven't listened to a Nautilus.
I just have a quick question building a golf cart for my son we bought a free air subwoofer thinking that I can just cut a hole in the side of the cart put the sub in it would that be efficient enough to be an intimate baffle
I doubt it. Unless the panel is sufficiently large, the back waves will cancel the front waves which will translate in lack of bass. You need some kind of enclosure.
Thank you, great video. I've a question, my speaker (selenium 8MB4P) has a Qts of 0.76, an Fs of 105 Hz and my EBP is about 120. For Qts I need an infinite Baffle, and for EBP a bass reflex, what kind of enclosure could be the best option? And how can I do an infinite baffle? Sometimes I think I have a rare kind of speaker 😅
Theoretically, an infinite baffle is also an oversized sealed box. In your case, anything above 25 liters (sealed box) would be an "infinite baffle". You could also go for a bass reflex box to gain some low-end extension at the expense of linearity.
@@AudioJudgementThank you Marius, I don't get the whole video at a first time (my English is not perfect yet), in case of an bass reflex, how can I predict the frequency response? because the tables I seen in Loudspeaker Design Cookbook has just a Qts max of 0.7, and measuring my Qts (by your REW method in another video) i obtain a 0.9 😅, definitively looks like my speaker is playing me a joke... it don't want to be enclosured 😅
is there any logic in production of speakers fro a specific company? Lets say do they think .. you are going to pair the XT25 BG 60 with the HDS-P830874 or is just random? based on marketing reasons? why for most brands are no suggestions on enclosure, best match or crossover?
When it comes to the companies which make the end product (loudspeaker box). They usually start with the box, because aesthetics and size matters most. From that point they reverse engineer the speaker driver and design a speaker which is best suited for that enclosure. When it comes to companies which make just speaker drivers, for the average DIY-er, they try to make drivers in each category (subwoofer, woofer, mid-bass, midrange, full range, tweeter) for each price bracket. I don't think they try to match them. Maybe occasionally. However, I've seen passive radiators which where made specifically for an active speaker which was mentioned in the spec sheet.
hallo i put my parameters in a calculator and it says i have ebp 101.. a sealed box but my qts=0,48 below 100 ebp = selead.. what is your advice ? can i use the midbase driver in a sealed box ? Mvg Jermain
Sealed or Ported calculation is different it is fs divided by qes so a speaker with qts 0.52 fs 65hz qes 0.62 recommended ported in your example you recommend sealed. Which one you recommend in this case?
To me looking at qts is just a quick guideline on which enclosure would work well with that particular driver (linear response). That doesn't mean you can't put a 0.52 qts speaker in a ported enclosure if you want more bass output. EBP is an indicator used by many software programs to determine which enclosure is best, but I still prefer quickly judging the speaker by its qts.
You pretty much need to model the frequency response of the speaker inside a box and then compare it to another. But if you want an answer that might not always stand true, the one with the larger moving mass will pump lows.
Hello, I was measured T&S parameters of 30w local speakers when I put DC resistance and diameter that time one message was shown me DC resistance is greater than impedance value , so can I do for that message to eliminate that error and get correct value. I am using REW software.
Nice video explanation. I'm interested in building a small, around 27 liters speaker cabinet for a full-range SB Acoustics SB20FRPC30-8 and I found that Qts is 0.45 and the Efficiency Bandwidth Product (EBP) is 83. Does it mean that this speaker driver is more suitable for a ported speaker or is it ok for a sealed speaker cabinet?
Either enclosure will work. However, 27 liters is too small. If you want to go for bass reflex you need around 100 liters of volume. As a result, go for sealed.
@@AudioJudgement thanks for your re[ly. Yes, a ported enclosure needs more volume but is it a 27 liters speaker cabinet also too small for a sealed enclosure or just too small for a ported enclosure?
Thanks for your highly informative video, I have to confess, I was very surprised to see my comment as the trigger for this video and I can't seem to feel a great deal of gratitude for your efforts. Thanks and I look forward you next video about loudspeakers. BTW do you have as much to share about amplifier design as you have on loudspeaker design.
Haven't studied amplifiers that much. Although I would like to learn in the future how to make DIY amps. If I do, I'll make sure to share how to do it :)
Hi your 620th subscriber here your videos are really easy to understand my question is what are your views on a quater wave transmission line enclosure for say a 2 way design and can u elaborate different types of transmission line designs and their applications and pros and cons. I would really appreciate your input on this. lastly what qts does a transmission line preffers
I really don’t have much experience with transmission lines. You can see in my videos my first attempt at a TL. Anyway, Qts should be around 0.7, as it basically plays in free air (just like an open /infinite baffle)
@@AudioJudgement I also struggled with speaker choice for a transmission line. I ended up assuming that a TL behaved more like a ported enclosure as it tends to control the driver somewhat with reflected waves similar to a ported enclosure so I went with a low Qts ~0.28 and it seemed to work well. I recently posted my design info but I don't think it has shown up yet (awaiting screening I think).
@@jimgardiner1558 Yeah, sorry, I deleted that comment. It contained 2 long links that looks suspicious to me. I was probably wrong, but I avoid downloading stuff from sources I don't know.
Audio Judgement Understandable. The 1st link was a paper I wrote and the 2nd link was an Excel spreadsheet. I might try posting it as a “WordPress” document on my own channel or as a blog. I don’t have much experience with this sort of thing yet.
I have 4 12s sealed on a ranger xlt what do you think should be done for the best Sound quality because I feel I reached a limit after 2 12s I have no clue what would sound best I want to make two 6th orders with a isobaric setup or should I make one big 6th order using Rockford p2 at the moment thinking about p3 looking for the least amount of mechanical noise! I also want that chest hit
You probably reached a limit after 2 12s, because your amplifier power is the same. It doesn't matter how many speaker you add after that, if you don't feed them enough power.
Audio Judgement I must be really choking the amps for power going to be upgraded to p3s with a t2500bd1 In probably a year from now because of its cost but I do believe that is my problem the p3 is 600 rms and p2 are 400 but my electrical should be on point with a few batteries
That’s JL Audio’s secret. Low Fs (21Hz) and high Vas (124 liters). So you put it in a smaller box that raises the F3 to 31 Hz. 31 Hz is acceptable in a car audio enclosure.
interesant cu qts-u asta ... Dar daca difuzorul e facut pentru cutie inchisa si canta la 60 de hz ( de exemplu ), in reflex canta la 40hz ... Alt battle :)) !!! Daca vrei sa scoti perfectiune, construiesti 3-4 incinte diferite si asculti care canta mai bine, pe gustul tau :D Am vazut ca ai facut asta ... Ma asteptam ca cea bass reflex sa sune cel mai tare, dar bass reflexul de multe ori pacaleste ... Am vazut ca ai pe masina incinta din fibra, cum suna fata de cele pe care le-ai facut pentru acel test ? Mai bine, mai rau ... Sunt curios :)
Doode. Awesome material. Can you please make you voice 6db higher? I can't hear shit while watching your videos in subway with maxed out volume. Your voice is very low pitched (:
Great video. Want an idea or a video to make. Take a junk unknown subwoofer. Go through the process and make it great. Nobody goes through the complete steps.. spit facts and numbers but never prove it. I've read all that stuff but still isn't clear. But countless videos boast all the theory, but no real practical. Why did you choose that size, and build it. Test it, prove your theory. I love your videos, but you asked for a topic
I've literally been struggling to determine how to pick what speakers would work in a sealed enclosure and this was the best guide I could find anywhere, thank you so much for this. I'm so glad that I found your channel and I have subscribed and will be perusing your vids to gain all the nuggets of knowledge I can!
You're going to be successful watch!
exact ce cautam. poate faci un video si despre forma incintelor sau care e jmecheria cu subwooferele cu difuzorul jos, cu fata la podea.
Excelent video! Very important information and with a very clear explanation ! Just what I wanted to understand about TS parameters. Now I do understand what the numbers means! Thanks
you are doing a Wonderful contribution to audio !!!!
How do you work backwards? Let’s say you want to upgrade the drivers in your MTM speaker cabinet to better ones.
You would measure the inside volume of the cabinet and the port, but then how do you determine which drivers would fit well in that enclosure?
Thanks!
well explained..always waiting for your vodeos..thank you.
Such jewels of information on this channel and only 4k subs. Its unfair and criminal.
Like the video alot- I was wondring what are the parameters used to determine the size of an acoustic suspension, ported and Transmission line design?
The best video on this subject!
I got my answer why my calculated volume is coming with a negative sign.
Now, what should be done for small speakers with Qts value more than 1.2?
Most likely this kind of speaker will play as a woofer so not much suitable for low freq. Usually high qts means the speaker is stiff and have good excursion control, again its not good for low freq. If it was me ill just make a sealed box to enhance excursion control or a ported box with high tunning like 80hz or whatever is the speaker fs and make it work as midbass, then you should have another speaker for lower freq.
Excellent video Marius, greetings from México ✌️
Thanks brother. So it's best to use 3 type of BASS when setting up a sound system ??? Because all 3 type is relevant to the different types of MUSIC u will have to PLAY . !!!!!!!! Don't u think
Thank you very much for the information in so simple words. Grateful indeed.
Hi, Hello,
I would like to ask question about right volume of sealed enclosure for speaker DaytonAudio PS95 8 3 1/2" Point Source Full Range Driver 8 Ohm. Every calculator gives me different sugestion about volume, so Im quite confused...Can you give me advise, what is the right size for this speaker?
Fs = 119,8 Hz , Qts = 0,72 , Vas = 0,94 l
Ok hello nice to meet you my name is Harold . I have been playing with audio from 8-10 years old . At 47 now every thing has gotten so tech now but I’m enjoy the learning , not to good on mart but as far as experimental yes just to see the out come ! Had a pair of Rockford p1 10” 250rms 500 peak playing with a nippon tubo 12 “bass cannon” the numbers does not match 12s it’s a 1.4 cf tube with a 18” long port at 22 sq inch . I have mounted a 10 half way seald aginst the top ten rear one faced up with the other faced up so isobaric sealed 0.7 between them 0.7 ported then test sound descent not outstanding. But I had a sealed 12” 1.2 cf square box that I turn the tube into it playing now two tens isobaric into a sealed box very big change it really needs just by listening to it the 1.2 ported and behind the 1st 10 then sealed .07 the other 10 then sealed plying into 0.7 kind reverse every thing I got! Of course there was no planning or thinking it was just to see what isobaric does never been close to one before or listen to one on,y pictures on the net ! And I’m not sure if you can or not put isobaric sealed playing into sealed I’ve seen it ported between and to the out in both ways ant together also seen it seald between but never playing into sealed! That brings me to the ? What order is this I’m calculating 4th order isobaric band pass with bad cubic feet numbers it has a good tone and hits decently hard but the low bass is killer accurate I found out one big thing isobaric helps control a lot of distortion that happens even with out the front sealed box I could tell a difference oh I’m running a kenwood in dash kickin-x704 with a audio control epecenter off 110ac converter into a Behringer km750 concert amplifier in a 20x16 8’ wall sealed garage “it’s insulated and plywood all 5 sides setting on 6” concrete” tanks fo all your information I’ve got a skar skv2500 and ax15 sundown audio v2 wanting to build areo port or 4th,6th order for the rear of my Toyota 4Runner I like what you shown here you got my choice down to areo or 6th order I currently have it in a sealed 3.0 box with a 10 k rockvilleRPA16 concert amp it rocks dude it knocks stuff of the cabinet the walls and refidgerator I also run the epecenter on it and half volume I can tell that’s plenty they both perform so well I’ve never had any thing with this much power back to the 4 runner I’m a welder/fabrication expert with Steele descent with wood I’ve placed an extra 220 amp alternator with a belt configuration added a old water pump pulley to my bottom drive off the crankshaft on the motor with 1 battery under my hood 650 can deep cycle marine battery extra volt gauge and light inside for this extra charging system that will have a 750 xs power agm motorcycle battery and a cap I’m thinking 5-10 fard I’ve got breakers and fuses for all of this will have 8” ds18 component set in doors with Rockford punch 200 on tweeters and arc audio 900.1 kar series on the 800watt 8s so I kinda need help with an space that’s 40 inches wide 24 inches long and 24-40 tall. I could go 2x15s if I want to I think they are1500 watt subwoofers what do you think I’m almost there I’m gonna use birch plywood they say it’s stronger and lighter than mdf/particle wood and with 2x15 subs how about never seen face to face isobaric sealed in the middle of the box with two different size ported chambers tune 1 real low like in the 20s and the other side in the 40s that’s what I’m aiming for I’ve even thought about building half of the isobaric loading and have it were latter on I could build the other half and sub then put them together to achieve that isobaric 4th or I guess it could be tuned to 6th order by porting the middle ? Let me know what you think I enjoy this knowledge you share and highly appreciate you for teaching I need to learn more before I can make the judgement of my box problem I have ask for advise from two others on line one no reply the other guy just throws out a basic slot port box I could go on a box building site and do my self the one thing I know for sure I want areo port or ports no matter they are more efficient but the grafts don’t lie you can see the big change in the lines from a slot port to a areo port I have always built seald boxes I’ve just recently got back into this audio game heavy the last year and half and seen all this new to me ports and the technical part of it is way above my head I’m learning slowly I want a good sounding over the broadest band but really low fq bass I think I can get it I know there’s a trade off but I know I don’t want a SPL build we’re it’s only good for 1 fq I’d like to have the range of that 6 th order you did with the 10 “ JL we’re it came in early in the low hz and hung in there to 80 and didn’t drop real bad till after100hz I’m thinking to myself if I hit around 100 hz on my highs decent and 20 to 80 be really killer I’d be plenty happy
Very much helpful and informative video. Please make a video on subwoofer cabinet designing.
I have a 12 inch midbass horn box how do I work out the vas
Big thank you for explanation! Really great content!
Thank you very much, but can you explain which speaker for passive radiator enclosure?
If it’s good for bass reflex it’s good for passive radiator as well.
@@AudioJudgement thank you very much :D
Can you do some videos on 6th order bandpass....specifically series tuned 6th order bandpass...and how important is the ratio or what should the ratio be
Hi, my speaker has a qts of 1,3
What enclosure should i use? :)
Thanks for your advice but I love sony home theater sub bass. what type of enclosure they use please explain... And I have TB subwoofer W5-1138SMF can I design box like that
Can you make one video explaining how to apply QE and boost the lower octaves of sealed subwoofer please ... Let's say a sealed subwoofer is rolling off at 30hz, and if we want to push it down to 20hz with EQ, how we can do?? And pros and cons, and limitations etc .
Seems like a good idea. I'll consider it for the future.
@@AudioJudgement wonderful !! Thanks a lot for reply !!
www.diyaudio.com/forums/subwoofers/362350-ts-parameters-decide-eq-driver-handle.html
That's a question I asked in a forum and some explanation is given by some nice people. (I'm just sharing for reference)
Hello sir i have eminence alpha 12 american standard series 150 whatts speaker
Parameters are as below
Qts is 0.77
Vas is 121.5 liters
Ebp is 56
Fs is 49 hz
So how much quantity of box that is encloser should i do
Means lebght and height and widht
Calculation formula can you send me sir
I hope u will tell me
Plz sir plz plz plz
I hope u will reply sir
Great video, I am about to finish the DIY T/S test cable you described building in one of your videos (great one) and I can't wait to run some measurements on some drivers I have laying around.
In your last video you outlined four factors that need consideration with regards to optimizing box volume to driver Vas, Qts and Fs as well as EBP.
As a DIY speaker builder, I would like to know how to determined the optimal box volume, once I have all of the relevant T/S parameters.
Let me simplify this further - Once I got real T/S parameters of my driver, I want to plug in the numbers into some online program (preferably free) or formula, and get the optimized box volume according to acoustics suspension or ported design (depending on the driver, of course).
Regarding your low subscription numbers - Unless you come up with some viral video, this process takes time and effort. It requires having more on line videos appealing and getting (hooking) people with shared interest.
Thanks for your videos and knowledge sharing
Search for WinISD. It’s a free app for box modeling
What about EBP? Rockford P3D3-10 recommends either sealed or ported. But, winISD Pro and other calculator indicate EBP of 44, thus should run sealed only. So then why would Rockford say and give specs for a ported box design?
--I thought that you always run the speaker at double it's resonant Hz or higher. But, no? So, I can design box for ... say... 30 Hz, even though response spec. is not given by Rockford. Or at least I can't find it.
You don't "run the speaker at double its resonant frequency". I've seen stupid guidelines like that before. Like in a 4th order bandpass, the ported chamber needs to be twice as large as the sealed chamber, or some other weird ratio. These are made up "rules". You simply model the frequency response, and if it looks according to your goals, then it's good. It doesn't matter that it doesn't follow some ratio a guy mentioned on a forum 30 years ago. Regarding EBP, yes, it's a way to determine what type of box you should go for. Used in WinISD and also mentioned in the Loudspeaker cookbook. I don't particularly use it though. If I take, for example, a midrange driver, EBP will almost always recommend a ported box (because of higher FS, EBP will most likely be over 100) and people always put midrange speakers in sealed enclosures (in talking about midrange drivers in 3way speakers). It's not black and white. You need to factor multiple parameters when deciding the enclosure type. So, if I want to simplify things, I just like to take a quick glance and Qts and form a rough idea on what enclosure will work best.
Agreed, these ratios on 4th order bandpass are misleading, been researching about them for my design
I also have a Rockford sub and Winisd says it has an Epb of 23 and recommends closed/bandpass 4th but the manual says either sealed or ported
@@rogersingh3918 Ya. So, I guess I'm not the only one who picked up on something like that. I ended up going with a JL 10W1v3-2, mainly because it was the easiest in winISD to tune for my RAV4s small real estate problem.
But, I had the sub for like 3 weeks. I am just finishing the enclosure. I just don't have time.
But, I've seen people in DIYMobileAudio talking crap about P3s, yet when I model them, they seem to perform very well.
Any thoughts?
@@RobHTech agreed, I have modelled both 4th and 6th order bandpass using Winisd and Bass box bro 6 and they both have an advantage in output vs regular ported according to RF specs. RF made their subs so they can work on either sealed or ported enclosures, the sub I've got is the RFP punch 3212 and it works great in a ported box, will be louder in 4th or 6th according to the modelling software, have not decided as yet whether 4th or 6th
Question, why are people making enclosures that look like a long maze? Is there a benefit for a “long path port”?
That's a transmission line. There are pro's and cons to that type of enclosure. Sometimes, that might be just a normal bass reflex with a very long port. There is no benefit for a long port. It's just a necessity to tune a box at a very low frequency
Do back reflections from the back of the box actually cause problems for a speaker driver? Does poly fill really help? I have read only natural wool is useful. What about adding diffraction panels ? B&W nautilus was designed to remove back waves. I have never heard a pair, have any of you?
Depending on which frequencies you want to absorb different materials will work better. You need denser for lower frequencies. And yes, standing waves, if they are bad enough, can cause the enclosure to "ring". Adding diffraction panels can help also. And no, I haven't listened to a Nautilus.
I just have a quick question building a golf cart for my son we bought a free air subwoofer thinking that I can just cut a hole in the side of the cart put the sub in it would that be efficient enough to be an intimate baffle
I doubt it. Unless the panel is sufficiently large, the back waves will cancel the front waves which will translate in lack of bass. You need some kind of enclosure.
Thank you, great video. I've a question, my speaker (selenium 8MB4P) has a Qts of 0.76, an Fs of 105 Hz and my EBP is about 120. For Qts I need an infinite Baffle, and for EBP a bass reflex, what kind of enclosure could be the best option? And how can I do an infinite baffle? Sometimes I think I have a rare kind of speaker 😅
Theoretically, an infinite baffle is also an oversized sealed box. In your case, anything above 25 liters (sealed box) would be an "infinite baffle". You could also go for a bass reflex box to gain some low-end extension at the expense of linearity.
@@AudioJudgementThank you Marius, I don't get the whole video at a first time (my English is not perfect yet), in case of an bass reflex, how can I predict the frequency response? because the tables I seen in Loudspeaker Design Cookbook has just a Qts max of 0.7, and measuring my Qts (by your REW method in another video) i obtain a 0.9 😅, definitively looks like my speaker is playing me a joke... it don't want to be enclosured 😅
I have a video on how to design a ported subwoofer box. There you can learn how to model the frequency response.
@@AudioJudgement I watch it now, it's a great video! Thanks Marius!
When they say le 1.4 mh for a speaker what does that mean
It's the inductance of the voice coil measured in milli Henries
hmm, would 0.37 be okay for a sealed box?
Its fs is 32hz. Ported I would be down to an F3 of 38hz
I have to build an enclosure for my motorcycle.. 2 6in P16 speakers, in a custom enclosure that will fit in a 15in x 8in x 6in area... Ugh
Can I somehow calculate or measure Qts of my driver?
you can use Dats V3 to measure Qts
is there any logic in production of speakers fro a specific company? Lets say do they think .. you are going to pair the XT25 BG 60 with the HDS-P830874 or is just random? based on marketing reasons? why for most brands are no suggestions on enclosure, best match or crossover?
When it comes to the companies which make the end product (loudspeaker box). They usually start with the box, because aesthetics and size matters most. From that point they reverse engineer the speaker driver and design a speaker which is best suited for that enclosure. When it comes to companies which make just speaker drivers, for the average DIY-er, they try to make drivers in each category (subwoofer, woofer, mid-bass, midrange, full range, tweeter) for each price bracket. I don't think they try to match them. Maybe occasionally. However, I've seen passive radiators which where made specifically for an active speaker which was mentioned in the spec sheet.
Hey can I access that box modeling excel file anywhere?
Find the link in the description of this video: th-cam.com/video/Vf9ApmMFKTg/w-d-xo.html
hallo
i put my parameters in a calculator and it says i have ebp 101.. a sealed box but my qts=0,48
below 100 ebp = selead..
what is your advice ? can i use the midbase driver in a sealed box ?
Mvg Jermain
Sealed or Ported calculation is different it is fs divided by qes so a speaker with qts 0.52 fs 65hz qes 0.62 recommended ported in your example you recommend sealed. Which one you recommend in this case?
To me looking at qts is just a quick guideline on which enclosure would work well with that particular driver (linear response). That doesn't mean you can't put a 0.52 qts speaker in a ported enclosure if you want more bass output. EBP is an indicator used by many software programs to determine which enclosure is best, but I still prefer quickly judging the speaker by its qts.
Can you talk about headroom?
Some subwoofers gives a lot of punch , while others pumps lows, how can we decide what they do based on the T/S paramiters
You pretty much need to model the frequency response of the speaker inside a box and then compare it to another. But if you want an answer that might not always stand true, the one with the larger moving mass will pump lows.
Explanation is clear thanks.
Hello, I was measured T&S parameters of 30w local speakers when I put DC resistance and diameter that time one message was shown me DC resistance is greater than impedance value , so can I do for that message to eliminate that error and get correct value. I am using REW software.
You are probably measuring from 1 Hz to 20 kHz. Set your measurement range from 20 Hz to 20 kHz
Nice video explanation. I'm interested in building a small, around 27 liters speaker cabinet for a full-range SB Acoustics SB20FRPC30-8 and I found that Qts is 0.45 and the Efficiency Bandwidth Product (EBP) is 83. Does it mean that this speaker driver is more suitable for a ported speaker or is it ok for a sealed speaker cabinet?
Either enclosure will work. However, 27 liters is too small. If you want to go for bass reflex you need around 100 liters of volume. As a result, go for sealed.
@@AudioJudgement thanks for your re[ly. Yes, a ported enclosure needs more volume but is it a 27 liters speaker cabinet also too small for a sealed enclosure or just too small for a ported enclosure?
It's doable for a sealed enclosure. 40-45 liter would be nicer, but 27 will work. Fill it up with damping material and you will be fine.
Ty for the information
very informative video. thanks
Very good insight. Thanks!
Thanks for your highly informative video, I have to confess, I was very surprised to see my comment as the trigger for this video and I can't seem to feel a great deal of gratitude for your efforts.
Thanks and I look forward you next video about loudspeakers. BTW do you have as much to share about amplifier design as you have on loudspeaker design.
Haven't studied amplifiers that much. Although I would like to learn in the future how to make DIY amps. If I do, I'll make sure to share how to do it :)
To build box for it
Hi your 620th subscriber here your videos are really easy to understand my question is what are your views on a quater wave transmission line enclosure for say a 2 way design and can u elaborate different types of transmission line designs and their applications and pros and cons. I would really appreciate your input on this. lastly what qts does a transmission line preffers
I really don’t have much experience with transmission lines. You can see in my videos my first attempt at a TL. Anyway, Qts should be around 0.7, as it basically plays in free air (just like an open /infinite baffle)
@@AudioJudgement I also struggled with speaker choice for a transmission line. I ended up assuming that a TL behaved more like a ported enclosure as it tends to control the driver somewhat with reflected waves similar to a ported enclosure so I went with a low Qts ~0.28 and it seemed to work well. I recently posted my design info but I don't think it has shown up yet (awaiting screening I think).
@@jimgardiner1558 Yeah, sorry, I deleted that comment. It contained 2 long links that looks suspicious to me. I was probably wrong, but I avoid downloading stuff from sources I don't know.
Audio Judgement Understandable. The 1st link was a paper I wrote and the 2nd link was an Excel spreadsheet. I might try posting it as a “WordPress” document on my own channel or as a blog. I don’t have much experience with this sort of thing yet.
Muy buen video!
Helpful thanks
What a treat! Thanks!
I have 4 12s sealed on a ranger xlt what do you think should be done for the best Sound quality because I feel I reached a limit after 2 12s I have no clue what would sound best I want to make two 6th orders with a isobaric setup or should I make one big 6th order using Rockford p2 at the moment thinking about p3 looking for the least amount of mechanical noise! I also want that chest hit
You probably reached a limit after 2 12s, because your amplifier power is the same. It doesn't matter how many speaker you add after that, if you don't feed them enough power.
Audio Judgement I ran another amp to the two so I had 2 pioneer 8601s and a 8604
Doubling the power and the number of speakers will yield precisely +6 dB, so it’s kinda weird that you don’t perceive the upgrade.
Audio Judgement I must be really choking the amps for power going to be upgraded to p3s with a t2500bd1 In probably a year from now because of its cost but I do believe that is my problem the p3 is 600 rms and p2 are 400 but my electrical should be on point with a few batteries
Great stuff thanks
That’s JL Audio’s secret. Low Fs (21Hz) and high Vas (124 liters). So you put it in a smaller box that raises the F3 to 31 Hz. 31 Hz is acceptable in a car audio enclosure.
Jaja. Das schaffen die meisten hifiboxen noch nicht mal.
great video ! your new subscriber ! please make a video about DIY HIFI tube preamp ! thanks in advance !
interesant cu qts-u asta ... Dar daca difuzorul e facut pentru cutie inchisa si canta la 60 de hz ( de exemplu ), in reflex canta la 40hz ... Alt battle :)) !!! Daca vrei sa scoti perfectiune, construiesti 3-4 incinte diferite si asculti care canta mai bine, pe gustul tau :D Am vazut ca ai facut asta ... Ma asteptam ca cea bass reflex sa sune cel mai tare, dar bass reflexul de multe ori pacaleste ... Am vazut ca ai pe masina incinta din fibra, cum suna fata de cele pe care le-ai facut pentru acel test ? Mai bine, mai rau ... Sunt curios :)
Nu e vorba ca e din fibra. Suna bine ca e incinta inchisa. Suna cel mai bine cea inchisa dar nu la fel de tare fata de restul.
why car speakers dont have ports in doors
Because people prefer a door pocket instead of a bass reflex port. And the volume is too little to make a working enclosure there.
can you test professional audio please. theres a big hole in this field. great work.
El Cavalo likes your videos Mr. Lupetta :)))
If the qts of the speaker is 1.23 then
It's for open baffle / infinite baffle
Please define Qts and Fs deeply
Doode. Awesome material.
Can you please make you voice 6db higher?
I can't hear shit while watching your videos in subway with maxed out volume. Your voice is very low pitched (:
Damn you. I have bought your speaker measurement course on udemy (:
You give nice information but those beeps broke me. Can't keep on watching.
I know, sorry. Fixed this for newer videos.
Great video. Want an idea or a video to make. Take a junk unknown subwoofer. Go through the process and make it great. Nobody goes through the complete steps.. spit facts and numbers but never prove it. I've read all that stuff but still isn't clear. But countless videos boast all the theory, but no real practical. Why did you choose that size, and build it. Test it, prove your theory. I love your videos, but you asked for a topic
chico menos teatro y mas inforamicon.
Implying an enclosure is even necessary or desirable. Guards, take him away!
😂 One of these days I will try open baffle