Fantastic content as always. Please can you do a video for all us really small room guys? My room is 3mx5m, can you go over the considerations of surround speakers so close with two people sitting side by side and the room treatment needed to combat this if I go the normal route of having the screen on the short wall . Or, and I am really considering this, setting up to have the screen on the long wall, what treatment/speaker position considerations along with any pitfalls laying out in this orientation poses. I see the benefits as 2 to 3 people sitting together in one long row, mains being around 2M away and surround speakers being 1.5-2M away in this small space in that orientation.
I have had both ported and sealed subs, and used REW, etc. to take a look at them. The sealed subs sound tighter and cleaner and with room gain measure better, so I now solely use them. One thing I don’t like about these comparisons is that they always compare the same driver. The sealed subs have better bass, but not as much output. I had 2 15” sealed subs and 2 ported. I always felt the sealed subs need more output, but the quality of bass was superior. What I did was make 2 21” sealed subs from DIYSG flat packs, and now I have end game sub performance. It’s tight and gets me to output capabilities I will never fully utilize. I would always get sealed, and scale to the level I want vs. jump to a ported sub that is more or less a cheating way to get more output at the expense of quality.
Fully agree with you man. I think it's the port being out of phase that makes us hear the ported as inferior to the sealed design. Just a belief don't have any real data to back it up tho. Just means we gotta dsp those low lows in.
Enjoyed this one Matt. Thanks. One must not forget Matt is talking about highest level of quality only few ever heard. Ported subs are great.. to some level.
I use 5 12inch drivers in sealed subs 1 SVS sb2000 and 2 diy dual opposed subs, with Scanspeak discovery drivers and Hypex FA amps. Each diy sub has the output of a JL E112, the speakers are also sealed.
Parameters of the sub matter for the box. Usually low qts subs are ported and mid qts subs sealed, while high qts go open baffle. Low qts subs like those used in ported box, would require a very big box tailored to it. Box size changes the qts. Each has a trade off.
Room gain combined with multiple sealed subwoofers generally works out better in the long run. Servo controlled ported subs can be really impressive as well.
I just keep going back to I tihnk for most home theaters, which are fairly reasonably sized rooms, the ports aren't worth the degraded sound quality. Sure there are some bassheads which maybe ported would be better, but, a lot of where we run out of headroom is in the ultra deep bass stuff and if that's below the port tune the sealed may actually perform better in my experience. There are some low tuned ported subs that do great but can still get out of wack... and that's before I even go into placement of the larger ported boxes, sometimes the placements options of smaller sealed subs make them worth it alone! another great video thanks for the info!
I just purchased ex machina speakers and one of the reasons was to have a sealed speaker. Faster decay times and tighter group delay. Everything counts
Hi Sir All your videos are very informative but please do support your videos with pictorial and graphic material for better understanding. Could you please post your favourite frequency response curves for Home Theater and Stereo listening. I am yet to find a target room eq curve that sounds pleasing to my ears. For me it seems like a never ending search. Thanks a lot for all your videos. 😊
I was told that SVS will be revealing a flagship sub at CEDIA 2024, curious to see if it will be available in both a sealed and ported version, or stick with one over the other.
Another very informative and helpful video Matthew. In a basement theater with concrete floors and outside wall where there is very little flex and therefore tactile response (no detached floor), would you still recommend sealed over ported?
I was always wondering why i liked sealed better than ported even tho ported was always louder. I honestly believe that its the port being out of phase is the reason behind this conundrum. And if you absolutely need that extra output just means we gotta dsp it in. Everything great in life takes at least a little effort on your part.
My assumption for most of my life has been that the best bass reflex system is better than the best acoustic suspension system, but also orders of magnitude more difficult to design.
Great video Matt! Many good points were made and backed up by real people with real tests. Even then, there is so much more that can be discussed by this topic. Does calibration like dirac help ported subs sound closer in quality to sealed? If you could only afford 1 or 2 subs, are sealed still the way? Would the outcome of the test you did with Gene have been different if you compared the same size drivers? Ported subs also require less amp power to get to the same level of a sealed, how does that factor into efficiency? And last but not least, I definitely want to hear more about the ported subs that work in a sealed mode. Is the quality as good as a proper sealed design? What does the Monolith/ Perlisten designer say about them?? Looking forward to hearing more and thanks for the great content! It is ultra insighftul and has been extremely helpful in my HT journey!
Doesn’t look like any well constructed double blind studies support the notion of a qualitative perceptual difference when played within their design limits. But it would make sense that if one ignores the price difference, a sealed sub with the output (not around port tuning) of a ported sub is going to go into distress less soon.
Have you or has anyone ever heard a properly designed transmissionline subwoofer? I would love to, but cannot justify the space requirement. One thing I am curious about is, since the port of a properly designed TL is roughly as large as the effective piston area of the driver, the chuffing problem should be effectively mitigated. I know that high powered PA subs use huge ports, often close to the driver size, implying that most commercial ported subs have way too small ports for their deep tuning.
Which ported Monolith subs are you referring to in the video? I think they had or used to have budget ones. Are you referring to those or the standard THX line? I thought those were well known to have little to no chuffing /distortion.
Probably depends on usage as well. For movies and music that has a lot of bass like rap, hip hop I like ported subs. I prefer sealed for softer music (so called "critical listening")..
Can you seal one those giant monoprice ported subs? They have a 2000 rms power amp but they are ported. Can you seal those up and get the same equivalent performance as if it were a real sealed sub?
Go 4x JTR RS1 and integrate butt kicker advanced transducers into the system if you want extension into the single digits that hits with authority with high efficiency, if you got no budget go 4x RS2 with the butt kickers 👌🏼
Hey Matt, I've got 2 custom ported 12" Subs that don't chuff ever. 3" port about 17" long, tuned to 18Hz. However, I can't replicate that box and would like more and better output. Considering going sealed 12" x4 for 2 Sealed subs up front and 2 sealed subs at back. When you say more drivers and the related efficiency etc. please elaborate. Wouldn't I need to add amplifiers for each of my new subs ?
Mark, I think there’s too many variables to make a generalization, but depending on the wiring topology / net impedance of dual drivers in the same enclosures, you could likely get by with a single amp channel per enclosure. Not personally a big fan of plate amps myself; my very modest HT incorporates a pair of small sealed passive subs, miniDSP for EQ, time delay alignment and room curve, with one channel of ICEpower AC200 per enclosure. Are you envisioning mixing sealed and ported, or replacing with all sealed? To my mind, one of the advantages of sealed is not worrying so much about overdriving them with major amounts of unintended power below the tuning frequency, and with modern film content that’s a lot easier to do than with music only. A BW48dB HP filter a couple of Hz below the tuning frequency might be useful there?
As to the "efficiency" question, ... theoretically; - double the drivers yields 3dB - doubling power to a single driver yields 3dB - doubling driver count and power yields 6dB
@@FOH3663 Which I think Matthew stated as well. To answer Mark’s question again, yes the new subs would need one amp channel per enclosure but not necessarily per driver. Im personally a fan of passive subs and external amps with miniDSP EQ & alignment, but many new commercial packages include apps that could replicate much of that functionality. I note than many of the sub drivers marketed to DIY builders are 4ohms, so one needs to be careful in selection of amps when wiring them in parallel - the duty cycle at very high signal levels at 2ohms could stress many beyond SOA, or at the very least initiate protection circuitry at inopportune moments.
@@fonkenful I'm considering going all sealed, 4 Separate 12" sealed subs / enclosures and each powered by a Crown XLS Amp - Bridged. Mini DSP and room EQ - REW.. All the tools will be incorporated for best in room response and smooth bass integration. Thanks for asking and sharing!
@@FOH3663 This is a beautifully simplified overview, thank you so much for this. Seems you might be an engineer or a communications savant! Thanks again.
I'd rather go sealed and call it a day than jump through the hoops of dialing in a ported sub to not be farting up my room/trunk space. The less filters/eq'ing I need to sound good the better!
Thanks soo much for taking my question and putting this excellent video together. Since my last msg with you Ive researched room gain and now see what you are talking about. Ive modeled the 2 boxes in WinISD and applied room gain to both. The sealed box definitely has much low end extension but only below 10hz. The ported sub performs better from 10hz - 35hz with the peak being at the port tuning frequency (17hz) with +10db. When designing the box (a modified Full Marty) I took care to account for chuffing and I dont think I'd push them hard enough to hear it anyway. I believe you when you say sealed would sound better but I still think I prefer the overhead that comes with the ported design, especially seeing that Im only gaining SPL under 10hz. For anyone interested, I found a great video from "Toids DIY Audio" that explains room gain and puts it to the test. -design and explanation. th-cam.com/video/ckrtptREwpo/w-d-xo.htmlsi=YykNPVlrtWmAiQgu -and the payoff th-cam.com/video/mM7F6dWM_dc/w-d-xo.htmlsi=p2Fqkt6WStB0hu5L
With a ported sub, you hear the bass the whole time and you can’t really hear those delicate “base details” in low frequency… A sealed sub is really much much better for a more pleasant listening
This whole sealed vs ported debate is so tiresome. You failed to point out that the same rules apply to ported when discussing output deficiencies. If you are running into issues with port noise and such, you are likely pushing the sub too hard and need to either size up, or add more subs. I would challenge anyone to point out a sealed sub system vs a ported sub system in a blind test, assuming both setup’s are equally configured and calibrated. Having sufficient headroom is the correct answer in both cases. Edit: obviously this assumes sealed subs vs ported subs of equal quality and pedigree. A good example would be a system with JTR sealed subs vs a system with JTR ported subs.
Good point. And bang for buck the ported sub wins (often by a factor of two) until you overdrive it. Which means you can afford to size up the ported sub so that you have so much headroom you don’t ever get close to overdriving it….and still save money.
Fantastic content as always. Please can you do a video for all us really small room guys? My room is 3mx5m, can you go over the considerations of surround speakers so close with two people sitting side by side and the room treatment needed to combat this if I go the normal route of having the screen on the short wall . Or, and I am really considering this, setting up to have the screen on the long wall, what treatment/speaker position considerations along with any pitfalls laying out in this orientation poses. I see the benefits as 2 to 3 people sitting together in one long row, mains being around 2M away and surround speakers being 1.5-2M away in this small space in that orientation.
Thank you for your question. I’ll answer it in my upcoming videos
@@PoesAcoustics thanks Matthew
Thanks!
Fart cannons - good thing I’d just swallowed my last sip of tea at that point 😂
Thanks a heap for all these off-the-cuff 'dissertations'. This one was fun as well as informative.
I have had both ported and sealed subs, and used REW, etc. to take a look at them. The sealed subs sound tighter and cleaner and with room gain measure better, so I now solely use them. One thing I don’t like about these comparisons is that they always compare the same driver. The sealed subs have better bass, but not as much output. I had 2 15” sealed subs and 2 ported. I always felt the sealed subs need more output, but the quality of bass was superior. What I did was make 2 21” sealed subs from DIYSG flat packs, and now I have end game sub performance. It’s tight and gets me to output capabilities I will never fully utilize. I would always get sealed, and scale to the level I want vs. jump to a ported sub that is more or less a cheating way to get more output at the expense of quality.
Fully agree with you man. I think it's the port being out of phase that makes us hear the ported as inferior to the sealed design. Just a belief don't have any real data to back it up tho. Just means we gotta dsp those low lows in.
Very helpful!
Enjoyed this one Matt. Thanks. One must not forget Matt is talking about highest level of quality only few ever heard. Ported subs are great.. to some level.
I use 5 12inch drivers in sealed subs 1 SVS sb2000 and 2 diy dual opposed subs, with Scanspeak discovery drivers and Hypex FA amps.
Each diy sub has the output of a JL E112, the speakers are also sealed.
Parameters of the sub matter for the box. Usually low qts subs are ported and mid qts subs sealed, while high qts go open baffle. Low qts subs like those used in ported box, would require a very big box tailored to it. Box size changes the qts. Each has a trade off.
Thank you for the info 👍🏼🏴🇬🇧
Room gain combined with multiple sealed subwoofers generally works out better in the long run. Servo controlled ported subs can be really impressive as well.
I just keep going back to I tihnk for most home theaters, which are fairly reasonably sized rooms, the ports aren't worth the degraded sound quality. Sure there are some bassheads which maybe ported would be better, but, a lot of where we run out of headroom is in the ultra deep bass stuff and if that's below the port tune the sealed may actually perform better in my experience. There are some low tuned ported subs that do great but can still get out of wack... and that's before I even go into placement of the larger ported boxes, sometimes the placements options of smaller sealed subs make them worth it alone! another great video thanks for the info!
Also for variable tuning subs where you can seal the ports, are those effectively the same as fully sealed subs or do you notice a difference?
I just purchased ex machina speakers and one of the reasons was to have a sealed speaker. Faster decay times and tighter group delay. Everything counts
Trinnov waveforming content please!!!
Hi Sir
All your videos are very informative but please do support your videos with pictorial and graphic material for better understanding. Could you please post your favourite frequency response curves for Home Theater and Stereo listening. I am yet to find a target room eq curve that sounds pleasing to my ears. For me it seems like a never ending search. Thanks a lot for all your videos. 😊
I was told that SVS will be revealing a flagship sub at CEDIA 2024, curious to see if it will be available in both a sealed and ported version, or stick with one over the other.
Another very informative and helpful video Matthew. In a basement theater with concrete floors and outside wall where there is very little flex and therefore tactile response (no detached floor), would you still recommend sealed over ported?
I was always wondering why i liked sealed better than ported even tho ported was always louder. I honestly believe that its the port being out of phase is the reason behind this conundrum. And if you absolutely need that extra output just means we gotta dsp it in. Everything great in life takes at least a little effort on your part.
My assumption for most of my life has been that the best bass reflex system is better than the best acoustic suspension system, but also orders of magnitude more difficult to design.
Great video Matt! Many good points were made and backed up by real people with real tests. Even then, there is so much more that can be discussed by this topic. Does calibration like dirac help ported subs sound closer in quality to sealed? If you could only afford 1 or 2 subs, are sealed still the way? Would the outcome of the test you did with Gene have been different if you compared the same size drivers? Ported subs also require less amp power to get to the same level of a sealed, how does that factor into efficiency? And last but not least, I definitely want to hear more about the ported subs that work in a sealed mode. Is the quality as good as a proper sealed design? What does the Monolith/ Perlisten designer say about them?? Looking forward to hearing more and thanks for the great content! It is ultra insighftul and has been extremely helpful in my HT journey!
What sealed subs do you run? Diy or something off the shelf?
Doesn’t look like any well constructed double blind studies support the notion of a qualitative perceptual difference when played within their design limits.
But it would make sense that if one ignores the price difference, a sealed sub with the output (not around port tuning) of a ported sub is going to go into distress less soon.
Have you or has anyone ever heard a properly designed transmissionline subwoofer? I would love to, but cannot justify the space requirement. One thing I am curious about is, since the port of a properly designed TL is roughly as large as the effective piston area of the driver, the chuffing problem should be effectively mitigated.
I know that high powered PA subs use huge ports, often close to the driver size, implying that most commercial ported subs have way too small ports for their deep tuning.
Which ported Monolith subs are you referring to in the video? I think they had or used to have budget ones. Are you referring to those or the standard THX line? I thought those were well known to have little to no chuffing /distortion.
Depends on volume. Every port is chuffing at some point. Some people don't even get there because of how loud it is for them.
Probably depends on usage as well. For movies and music that has a lot of bass like rap, hip hop I like ported subs. I prefer sealed for softer music (so called "critical listening")..
Can you seal one those giant monoprice ported subs?
They have a 2000 rms power amp but they are ported.
Can you seal those up and get the same equivalent performance as if it were a real sealed sub?
I would say no, because of the driver qts parameter (how there driver reacts on back pressure).
Is t the 3db gain for doubling driver count only if they are “close”
It means in one box. Drivers distance isn't important so much because of the low frequencies they produced (long waves).
Go 4x JTR RS1 and integrate butt kicker advanced transducers into the system if you want extension into the single digits that hits with authority with high efficiency, if you got no budget go 4x RS2 with the butt kickers 👌🏼
Hey Matt, I've got 2 custom ported 12" Subs that don't chuff ever. 3" port about 17" long, tuned to 18Hz.
However, I can't replicate that box and would like more and better output. Considering going sealed 12" x4 for 2 Sealed subs up front and 2 sealed subs at back.
When you say more drivers and the related efficiency etc. please elaborate. Wouldn't I need to add amplifiers for each of my new subs ?
Mark, I think there’s too many variables to make a generalization, but depending on the wiring topology / net impedance of dual drivers in the same enclosures, you could likely get by with a single amp channel per enclosure. Not personally a big fan of plate amps myself; my very modest HT incorporates a pair of small sealed passive subs, miniDSP for EQ, time delay alignment and room curve, with one channel of ICEpower AC200 per enclosure.
Are you envisioning mixing sealed and ported, or replacing with all sealed?
To my mind, one of the advantages of sealed is not worrying so much about overdriving them with major amounts of unintended power below the tuning frequency, and with modern film content that’s a lot easier to do than with music only. A BW48dB HP filter a couple of Hz below the tuning frequency might be useful there?
As to the "efficiency" question, ... theoretically;
- double the drivers yields 3dB
- doubling power to a single driver yields 3dB
- doubling driver count and power yields 6dB
@@FOH3663 Which I think Matthew stated as well. To answer Mark’s question again, yes the new subs would need one amp channel per enclosure but not necessarily per driver. Im personally a fan of passive subs and external amps with miniDSP EQ & alignment, but many new commercial packages include apps that could replicate much of that functionality.
I note than many of the sub drivers marketed to DIY builders are 4ohms, so one needs to be careful in selection of amps when wiring them in parallel - the duty cycle at very high signal levels at 2ohms could stress many beyond SOA, or at the very least initiate protection circuitry at inopportune moments.
@@fonkenful I'm considering going all sealed, 4 Separate 12" sealed subs / enclosures and each powered by a Crown XLS Amp - Bridged. Mini DSP and room EQ - REW.. All the tools will be incorporated for best in room response and smooth bass integration.
Thanks for asking and sharing!
@@FOH3663 This is a beautifully simplified overview, thank you so much for this. Seems you might be an engineer or a communications savant! Thanks again.
I'd rather go sealed and call it a day than jump through the hoops of dialing in a ported sub to not be farting up my room/trunk space. The less filters/eq'ing I need to sound good the better!
Thanks soo much for taking my question and putting this excellent video together. Since my last msg with you Ive researched room gain and now see what you are talking about. Ive modeled the 2 boxes in WinISD and applied room gain to both. The sealed box definitely has much low end extension but only below 10hz. The ported sub performs better from 10hz - 35hz with the peak being at the port tuning frequency (17hz) with +10db. When designing the box (a modified Full Marty) I took care to account for chuffing and I dont think I'd push them hard enough to hear it anyway. I believe you when you say sealed would sound better but I still think I prefer the overhead that comes with the ported design, especially seeing that Im only gaining SPL under 10hz.
For anyone interested, I found a great video from "Toids DIY Audio" that explains room gain and puts it to the test.
-design and explanation.
th-cam.com/video/ckrtptREwpo/w-d-xo.htmlsi=YykNPVlrtWmAiQgu
-and the payoff
th-cam.com/video/mM7F6dWM_dc/w-d-xo.htmlsi=p2Fqkt6WStB0hu5L
With a ported sub, you hear the bass the whole time and you can’t really hear those delicate “base details” in low frequency… A sealed sub is really much much better for a more pleasant listening
This whole sealed vs ported debate is so tiresome. You failed to point out that the same rules apply to ported when discussing output deficiencies. If you are running into issues with port noise and such, you are likely pushing the sub too hard and need to either size up, or add more subs. I would challenge anyone to point out a sealed sub system vs a ported sub system in a blind test, assuming both setup’s are equally configured and calibrated. Having sufficient headroom is the correct answer in both cases.
Edit: obviously this assumes sealed subs vs ported subs of equal quality and pedigree. A good example would be a system with JTR sealed subs vs a system with JTR ported subs.
Good point. And bang for buck the ported sub wins (often by a factor of two) until you overdrive it. Which means you can afford to size up the ported sub so that you have so much headroom you don’t ever get close to overdriving it….and still save money.
PFF!
I think ported subs suck they just mess with the sound too much and makes it unbalanced
Exactly
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