2nd subwoofer for music - AVS Forum | Home Theater Discussions And Reviews
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post #1 of 26 Old 01-01-2020, 09:43 PM - Thread Starter
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2nd subwoofer for music

Happy new year to all of you guys

I am upgrading my home theater.
Projector ceiling speakers and amplifier are done it is now time for the subwoofer.

The room is 15 x 25 x 8.
The Screen is 112” wide on 2:39 format
I have made 9 16”x24”x4” acoustic panels.

My subwoofer is an end table design by neo dan 12 years ago. Around 10 cuft ported enclosure.
The driver is a Maelstrom 18x powered by a bridged ep2500 behringer and Equalized with a Mic200

This Subs shake the whole 3 levels of our house and is almost perfect for home theater.
However I also like music and for me it is not clean enough and do not produced the bass I d like to hear for concert.
so I would like to add a sealed sub with a 18” or even 24” driver.

I look at the Dayton UM18-22 with their kit for a 4cuft sealed enclosure and the SPA 1200 plate amplifier. I am also planning to add the Dayton audio wave link WLS 2.4Ghz as I can t run cable.

Will this subs sound different and makes the system unbalanced ?

I know a sealed produce less Bass than a ported but also cleaner bass.

This is why I am thinking of the 24” HS-24 MKIII.
Apparently it needs a 10 cuft for sealed enclosure which will makes it nearly the same dimension as my existing ported.
I have not find a plate amplifier for it.

FYI here is what have been replaced so far:
The epson 6500 with a 5050UB
The Yamaha RX-V663 withe a Denon RX 4500H
Added 4 ceiling speakers theater solution S80W

I will run eleven channel having the 2 center speaker powered by the old yamaha (the amplifier part only) and the sherwood 2x200Watt RMS will power the Right and Left

thanks for your help
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post #2 of 26 Old 01-01-2020, 10:16 PM
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2nd subwoofer for music

Quote:
Originally Posted by smoke90 View Post
Happy new year to all of you guys



I am upgrading my home theater.

Projector ceiling speakers and amplifier are done it is now time for the subwoofer.



The room is 15 x 25 x 8.

The Screen is 112” wide on 2:39 format

I have made 9 16”x24”x4” acoustic panels.



My subwoofer is an end table design by neo dan 12 years ago. Around 10 cuft ported enclosure.

The driver is a Maelstrom 18x powered by a bridged ep2500 behringer and Equalized with a Mic200



This Subs shake the whole 3 levels of our house and is almost perfect for home theater.

However I also like music and for me it is not clean enough and do not produced the bass I d like to hear for concert.

so I would like to add a sealed sub with a 18” or even 24” driver.



I look at the Dayton UM18-22 with their kit for a 4cuft sealed enclosure and the SPA 1200 plate amplifier. I am also planning to add the Dayton audio wave link WLS 2.4Ghz as I can t run cable.



Will this subs sound different and makes the system unbalanced ?



I know a sealed produce less Bass than a ported but also cleaner bass.



This is why I am thinking of the 24” HS-24 MKIII.

Apparently it needs a 10 cuft for sealed enclosure which will makes it nearly the same dimension as my existing ported.

I have not find a plate amplifier for it.



FYI here is what have been replaced so far:

The epson 6500 with a 5050UB

The Yamaha RX-V663 withe a Denon RX 4500H

Added 4 ceiling speakers theater solution S80W



I will run eleven channel having the 2 center speaker powered by the old yamaha (the amplifier part only) and the sherwood 2x200Watt RMS will power the Right and Left



thanks for your help

Not true at all that sealed is cleaner than a properly designed ported sub.

The problem with mixing sealed and ported subs (or differently tuned ported) is that you get cancellation near port tuning. At least if you are planning to run both at the same time.

What is the tune on your existing sub?

For a music oriented sub, I would suggest a pro driver. Since you’re already considering up to a 24”, lets look at some 21” options. The best bang for the buck is the LaVoce San214.50, but it is 8ohm only. The B&C 21ds115 is more expensive for slightly less performance, but is available in 4ohm. The Eminence NSW6021-6 is the most expensive and highest performance option. It is a 6ohm driver, but acts more like a 4ohm.

With those drivers for music, I would use a ported box in the 20-25hz range.

Speakerpower makes a plate amp (sp1-4000) that will drive the SI 24, or any of the 4ohm pro drivers.

Chris
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post #3 of 26 Old 01-02-2020, 07:05 AM - Thread Starter
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Quote:
Originally Posted by a77cj7 View Post
Not true at all that sealed is cleaner than a properly designed ported sub.

The problem with mixing sealed and ported subs (or differently tuned ported) is that you get cancellation near port tuning. At least if you are planning to run both at the same time.

What is the tune on your existing sub?

For a music oriented sub, I would suggest a pro driver. Since you’re already considering up to a 24”, lets look at some 21” options. The best bang for the buck is the LaVoce San214.50, but it is 8ohm only. The B&C 21ds115 is more expensive for slightly less performance, but is available in 4ohm. The Eminence NSW6021-6 is the most expensive and highest performance option. It is a 6ohm driver, but acts more like a 4ohm.

With those drivers for music, I would use a ported box in the 20-25hz range.

Speakerpower makes a plate amp (sp1-4000) that will drive the SI 24, or any of the 4ohm pro drivers.

Chris
This is the sub I did

https://www.avsforum.com/forum/155-d...-37-5-hwd.html

I think the tune is at 14hz if I am correct @Neo dan
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post #4 of 26 Old 01-02-2020, 07:09 AM
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Quote:
Originally Posted by smoke90 View Post
This is the sub I did



https://www.avsforum.com/forum/155-d...-37-5-hwd.html



I think the tune is at 14hz if I am correct @Neo dan


That would be a very low tune for a pro sub. Do you plan to use both subs together?

Chris
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post #5 of 26 Old 01-02-2020, 07:11 AM - Thread Starter
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Quote:
Originally Posted by a77cj7 View Post
That would be a very low tune for a pro sub. Do you plan to use both subs together?

Chris
Yes I do
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post #6 of 26 Old 01-02-2020, 07:17 AM
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Quote:
Originally Posted by smoke90 View Post
Yes I do

Do you have room for a second identical sub? Off the top of my head, a NSW6021 in that enclosure should work.
I can model it for you when I get home today if you’re interested.

Chris
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post #7 of 26 Old 01-02-2020, 11:04 AM
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Quote:
Originally Posted by a77cj7 View Post
Not true at all that sealed is cleaner than a properly designed ported sub.
Bingo. I think any improvement from a new sealed unit is likely to be expectation bias. I think you have an issue somewhere else in the system.


Edit; we've been having a GTG here for years, and ask any attendee, it's one of the best system ever heard, irrespective of $. It's 100% music. Subs are a pair of ported Maelstrom 18's.

“You are not special. You are not a beautiful and unique snowflake.” Chuck Palahniuk
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post #8 of 26 Old 01-02-2020, 02:01 PM
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A dual-opposed B&C 21 might be a candidate, look at the data-bass charts.

The 24 is also a good choice, it would have more low-end than the B&C's.
The 24 is also more efficient than most 18's and harder to bottom out.

The EP2500 is a fairly weak amplifier (but there are also far worse.)
You should look at upgrading to an FP14000DSP, or if you need fanless then SpeakerPower and a miniDSP.
The 14k can power 2 24's, or probably 4 21's without too much difficulty.

The oversimplified summary is:
ULF (1-30hz) requires cone-area x excursion.
Mid-bass (40-300hz) requires cone-area x powerhandling x efficiency

1-30hz is for earthquakes, helicopter blades, pipe organs and BassILoveU
30-300hz is for music and explosions, and everything-else.

Most car subs and other high-excursion drivers are optimized for ULF; PA woofers are optimized for mid-bass (they have low-mass cones and all the BL is focused on the first few mm's of travel, making them 95-102db/w/m @ 10mm's instead of 85db/w/m @ 40mm's)

Due the 24 having lots of cone-area, power-handling and efficiency is actually does very well for what it is; dual B&C 21's will eek out a bit more mid-bass for roughly the same cost, but suffers from lack of linear excursion at low frequencies.

There is no free lunch.
There is no such thing as a perfect woofer / box either, it's all a balance of compromises.

Ported subs have driver noise and port noise. Sealed subs only have driver noise.
Ported subs have chuffing and wind movement they have to deal with. I used to have ported subs from 2001 to 2008, my B&W's were also ported and with several hundred watts going to the woofers you could shoot puffs of air 20ft away, you'd be like "where is that draft on my feet coming from, OH it's the hole in the speaker/subs!" Fun for a bit but gets old fast, that's why I went all-sealed (I also happen to enjoy 1-10hz.)
I suppose one could blast the ceiling/wall with the port wind, instead of directly across the floor at the listeners.

Ported is great when you are on a budget and/or have a limited amount of cones. (Say just 1 or a few subs.)

Porting to 1-10hz isn't practical for most people, so you'll be trading single digits and a phase-shift at tuning.
With IB or sealed you generally don't have these problems.

The downside of sealed is that it only uses the front of the cone, so it isn't as efficient near tuning, thus more prone to bottoming and driver noise; and since the box is fighting the cone they also require more watts and generate hotter coil temperatures. But you don't have a 180 phase shift or wind to deal with, and the boxes can be made smaller without sacrificing mid-bass SPL.

The goal of HiFi is to reproduce all frequencies cleanly (preferably up to high-SPL too!)
1-2hz is octave 1
2-4hz is octave 2
4-8hz is octave 3
8-16hz is octave 4
16-32hz is octave 5
The very concept of a HPF on the ULF section is anti-HiFi, you are literally not reproducing all the octaves, thus no HiFi.
That said, there is NO POINT in trying to reproduce 1-15hz if you don't have the cone-area to actually generate some usable SPL.

Hann's theater is pretty much the Gold-Standard, and has 22 IB'ed 24's in it; claimed usable to ~3hz. (I believe it!)
That's enough displacement to kill an elephant.
System of the Century. Nobody is gonna be matching or exceeding that anytime soon...

Solving 30-300hz is fairly cheap, a dozen or half-dozen PA woofers will handle that with ease.
But each octave lower you desire, will end up costing you 4x the hardware and 4x the price.
Single digits is 1%er territory.

The other problem is, single digit bass is rare and fleeting, at least recorded with any strength that-is.
Out of a 3 hour movie there is only a few scenes with about ~3 seconds in duration of strong infrasonics in it, think EOT or WOTW's etc...
So not only is it expensive to reproduce, it's also rare and fleeting to encounter. A triple whammy. A hard pill to swallow for most 99%er's.

8 PA-460's is <$800. That's hella-cheap for that amount of total-cone-area and total-power-handling and total-efficiency!
Would 8 B&C 21's be better? Of course , but it is also approaching 5 figures... (for just a couple more db's.)
Iron Law etc etc.
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post #9 of 26 Old 01-02-2020, 02:43 PM
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OP, it sounds like your existing sub has plenty of oomph for ULF. Depending on the music you're listening to, and especially if you're talking a 'concert' experience, the content isn't emphasizing ULF.

Consider that what you may be missing is actually midbass. If you find yourself describing what's missing as 'punch' or 'slam', that's the mid-bass. A sealed UM18-22 is pretty exactly the wrong answer for missing mid-bass. In this case, your problem could be solved with a couple PA-460 VBSS's like BassThatHz suggests above.
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post #10 of 26 Old 01-02-2020, 06:05 PM
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Quote:
Originally Posted by BassThatHz View Post
A dual-opposed B&C 21 might be a candidate, look at the data-bass charts.

The 24 is also a good choice, it would have more low-end than the B&C's.
The 24 is also more efficient than most 18's and harder to bottom out.

The EP2500 is a fairly weak amplifier (but there are also far worse.)
You should look at upgrading to an FP14000DSP, or if you need fanless then SpeakerPower and a miniDSP.
The 14k can power 2 24's, or probably 4 21's without too much difficulty.

The oversimplified summary is:
ULF (1-30hz) requires cone-area x excursion.
Mid-bass (40-300hz) requires cone-area x powerhandling x efficiency

1-30hz is for earthquakes, helicopter blades, pipe organs and BassILoveU
30-300hz is for music and explosions, and everything-else.

Most car subs and other high-excursion drivers are optimized for ULF; PA woofers are optimized for mid-bass (they have low-mass cones and all the BL is focused on the first few mm's of travel, making them 95-102db/w/m @ 10mm's instead of 85db/w/m @ 40mm's)

Due the 24 having lots of cone-area, power-handling and efficiency is actually does very well for what it is; dual B&C 21's will eek out a bit more mid-bass for roughly the same cost, but suffers from lack of linear excursion at low frequencies.

There is no free lunch.
There is no such thing as a perfect woofer / box either, it's all a balance of compromises.

Ported subs have driver noise and port noise. Sealed subs only have driver noise.
Ported subs have chuffing and wind movement they have to deal with. I used to have ported subs from 2001 to 2008, my B&W's were also ported and with several hundred watts going to the woofers you could shoot puffs of air 20ft away, you'd be like "where is that draft on my feet coming from, OH it's the hole in the speaker/subs!" Fun for a bit but gets old fast, that's why I went all-sealed (I also happen to enjoy 1-10hz.)
I suppose one could blast the ceiling/wall with the port wind, instead of directly across the floor at the listeners.

Ported is great when you are on a budget and/or have a limited amount of cones. (Say just 1 or a few subs.)

Porting to 1-10hz isn't practical for most people, so you'll be trading single digits and a phase-shift at tuning.
With IB or sealed you generally don't have these problems.

The downside of sealed is that it only uses the front of the cone, so it isn't as efficient near tuning, thus more prone to bottoming and driver noise; and since the box is fighting the cone they also require more watts and generate hotter coil temperatures. But you don't have a 180 phase shift or wind to deal with, and the boxes can be made smaller without sacrificing mid-bass SPL.

The goal of HiFi is to reproduce all frequencies cleanly (preferably up to high-SPL too!)
1-2hz is octave 1
2-4hz is octave 2
4-8hz is octave 3
8-16hz is octave 4
16-32hz is octave 5
The very concept of a HPF on the ULF section is anti-HiFi, you are literally not reproducing all the octaves, thus no HiFi.
That said, there is NO POINT in trying to reproduce 1-15hz if you don't have the cone-area to actually generate some usable SPL.

Hann's theater is pretty much the Gold-Standard, and has 22 IB'ed 24's in it; claimed usable to ~3hz. (I believe it!)
That's enough displacement to kill an elephant.
System of the Century. Nobody is gonna be matching or exceeding that anytime soon...

Solving 30-300hz is fairly cheap, a dozen or half-dozen PA woofers will handle that with ease.
But each octave lower you desire, will end up costing you 4x the hardware and 4x the price.
Single digits is 1%er territory.

The other problem is, single digit bass is rare and fleeting, at least recorded with any strength that-is.
Out of a 3 hour movie there is only a few scenes with about ~3 seconds in duration of strong infrasonics in it, think EOT or WOTW's etc...
So not only is it expensive to reproduce, it's also rare and fleeting to encounter. A triple whammy. A hard pill to swallow for most 99%er's.

8 PA-460's is <$800. That's hella-cheap for that amount of total-cone-area and total-power-handling and total-efficiency!
Would 8 B&C 21's be better? Of course , but it is also approaching 5 figures... (for just a couple more db's.)
Iron Law etc etc.
I'd just like to thank you for putting the subwoofer requirements together so succinctly. This would be stickied / shared all over.

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post #11 of 26 Old 01-02-2020, 07:03 PM - Thread Starter
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Quote:
Originally Posted by a77cj7 View Post
Do you have room for a second identical sub? Off the top of my head, a NSW6021 in that enclosure should work.
I can model it for you when I get home today if you’re interested.

Chris
Thank you Chris
Really appreciate it.
At this stage I am still looking at my option
And yes this room is 100% dedicated to home theater so as it is 375 sqft I had plenty of room
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post #12 of 26 Old 01-02-2020, 11:12 PM
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Quote:
Originally Posted by smoke90 View Post
Happy new year to all of you guys
Happy New Year to you too !


Quote:
Originally Posted by smoke90 View Post
However I also like music and for me it is not clean enough and do not produced the bass I d like to hear for concert.
so I would like to add a sealed sub ... Will this subs sound different and makes the system unbalanced ?
You can't mix ported and sealed subs in the same passband without some negative effects.

Sealed subs tend to maintain the sound phase while the ported subs start gradually lagging the phase below 2x port tuning frequency. The reason for that is in the nature of the ported subs - below 2xF tuning the SPL generation starts shifting from the driver cone FRONT side to the port opening where the sound energy comes from the BACK of the driver.

Let's take a 20Hz-tuned ported sub. The 30Hz fundamental tone would get delayed by roughly 90deg relative to the 40Hz and above - that would be like moving the sub further away by 10' for the 30Hz tone only .
For a 25Hz tone the delay would get close to 120deg and the timing difference would be almost like placing the sub 15' further back for that frequency only.

For music where the timing between fundamental tone and it's harmonics is important that delay makes the instruments sometimes sound unnatural.

OTOH in movies the ported subs delays don't draw your attention since nobody really knows how an explosion should sound like. Nobody is really into the musicality of an King Kong chest thumping or a grenade explosion.

Besides that ported subs phase delay causes cancellations when you mix sealed sub and ported sub in the same passband. The phase differences below 2xF port tuning causes cancellations which intensity is frequency dependent and it increases when frequencies get closer to the port tuning frequency.

You can use ported sub for movies and sealed sub for music as long as they don't play in the same time.

//
... someone said "Music is Art, Sound is Engineering" ...

Last edited by Will P; 01-02-2020 at 11:17 PM.
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Quote:
Originally Posted by smoke90 View Post
Thank you Chris

Really appreciate it.

At this stage I am still looking at my option

And yes this room is 100% dedicated to home theater so as it is 375 sqft I had plenty of room


Sorry, just got in from painting my current enclosure project. I’ll get that model run for you tomorrow.

Chris
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post #14 of 26 Old 01-03-2020, 02:35 PM
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So, what happen when we have bassreflex main speakers? How they mix with ported subwoofers, there are also cancellations?
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So, what happen when we have bassreflex main speakers? How they mix with ported subwoofers, there are also cancellations?


Doesn’t matter on subwoofer type in this case, just the port tuning of the mains. If you run the mains down to port tuning, and run subs at that frequency, you will get cancellations.

Generally speakers are crossed well above port tuning when subwoofers are used, so it isn’t a problem.

Chris
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2nd subwoofer for music

Quote:
Originally Posted by smoke90 View Post
Thank you Chris

Really appreciate it.

At this stage I am still looking at my option

And yes this room is 100% dedicated to home theater so as it is 375 sqft I had plenty of room


Tried to model it for you, but the pics are gone from the thread you linked. Without port length, I can’t do anything useful.

Chris
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post #17 of 26 Old 01-03-2020, 08:06 PM - Thread Starter
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Quote:
Originally Posted by BassThatHz View Post
A dual-opposed B&C 21 might be a candidate, look at the data-bass charts.

The 24 is also a good choice, it would have more low-end than the B&C's.
The 24 is also more efficient than most 18's and harder to bottom out.

The EP2500 is a fairly weak amplifier (but there are also far worse.)
You should look at upgrading to an FP14000DSP, or if you need fanless then SpeakerPower and a miniDSP.
The 14k can power 2 24's, or probably 4 21's without too much difficulty.

The oversimplified summary is:
ULF (1-30hz) requires cone-area x excursion.
Mid-bass (40-300hz) requires cone-area x powerhandling x efficiency

1-30hz is for earthquakes, helicopter blades, pipe organs and BassILoveU
30-300hz is for music and explosions, and everything-else.

Most car subs and other high-excursion drivers are optimized for ULF; PA woofers are optimized for mid-bass (they have low-mass cones and all the BL is focused on the first few mm's of travel, making them 95-102db/w/m @ 10mm's instead of 85db/w/m @ 40mm's)

Due the 24 having lots of cone-area, power-handling and efficiency is actually does very well for what it is; dual B&C 21's will eek out a bit more mid-bass for roughly the same cost, but suffers from lack of linear excursion at low frequencies.

There is no free lunch.
There is no such thing as a perfect woofer / box either, it's all a balance of compromises.

Ported subs have driver noise and port noise. Sealed subs only have driver noise.
Ported subs have chuffing and wind movement they have to deal with. I used to have ported subs from 2001 to 2008, my B&W's were also ported and with several hundred watts going to the woofers you could shoot puffs of air 20ft away, you'd be like "where is that draft on my feet coming from, OH it's the hole in the speaker/subs!" Fun for a bit but gets old fast, that's why I went all-sealed (I also happen to enjoy 1-10hz.)
I suppose one could blast the ceiling/wall with the port wind, instead of directly across the floor at the listeners.

Ported is great when you are on a budget and/or have a limited amount of cones. (Say just 1 or a few subs.)

Porting to 1-10hz isn't practical for most people, so you'll be trading single digits and a phase-shift at tuning.
With IB or sealed you generally don't have these problems.

The downside of sealed is that it only uses the front of the cone, so it isn't as efficient near tuning, thus more prone to bottoming and driver noise; and since the box is fighting the cone they also require more watts and generate hotter coil temperatures. But you don't have a 180 phase shift or wind to deal with, and the boxes can be made smaller without sacrificing mid-bass SPL.

The goal of HiFi is to reproduce all frequencies cleanly (preferably up to high-SPL too!)
1-2hz is octave 1
2-4hz is octave 2
4-8hz is octave 3
8-16hz is octave 4
16-32hz is octave 5
The very concept of a HPF on the ULF section is anti-HiFi, you are literally not reproducing all the octaves, thus no HiFi.
That said, there is NO POINT in trying to reproduce 1-15hz if you don't have the cone-area to actually generate some usable SPL.

Hann's theater is pretty much the Gold-Standard, and has 22 IB'ed 24's in it; claimed usable to ~3hz. (I believe it!)
That's enough displacement to kill an elephant.
System of the Century. Nobody is gonna be matching or exceeding that anytime soon...

Solving 30-300hz is fairly cheap, a dozen or half-dozen PA woofers will handle that with ease.
But each octave lower you desire, will end up costing you 4x the hardware and 4x the price.
Single digits is 1%er territory.

The other problem is, single digit bass is rare and fleeting, at least recorded with any strength that-is.
Out of a 3 hour movie there is only a few scenes with about ~3 seconds in duration of strong infrasonics in it, think EOT or WOTW's etc...
So not only is it expensive to reproduce, it's also rare and fleeting to encounter. A triple whammy. A hard pill to swallow for most 99%er's.

8 PA-460's is <$800. That's hella-cheap for that amount of total-cone-area and total-power-handling and total-efficiency!
Would 8 B&C 21's be better? Of course , but it is also approaching 5 figures... (for just a couple more db's.)
Iron Law etc etc.
This is a lot of info to educate myself
I start to realize that waht I may be missing is not from the 10-30hz as I saw the curtain or the door moving with the low frequency from the subs bit more in the low cross over
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post #18 of 26 Old 01-03-2020, 08:08 PM - Thread Starter
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Originally Posted by a77cj7 View Post
Tried to model it for you, but the pics are gone from the thread you linked. Without port length, I can’t do anything useful.

Chris
Do not worry at this stage I think my issue is not in the sub
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post #19 of 26 Old 01-03-2020, 08:45 PM
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if you have dsp, such as minidsp or something, the lavoce 21" in an MBM style cab would be great.

approx. 7 cubic feet tuned to around 27hz.

high pass the la voce at 27hz 2nd order (12db/oct) and low pass your other sub 4th order (24db/oct) under it.

they will offer combined headroom around 30Hz, you will likely have room gain supporting the LLT under that and the la voce has headroom above.

that should get you lots of headroom on the low end and high efficiency on the middle and upper end which is what you are looking for.
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post #20 of 26 Old 01-04-2020, 08:26 AM - Thread Starter
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post #21 of 26 Old 01-05-2020, 06:21 PM - Thread Starter
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Quote:
Originally Posted by BassThatHz View Post

Solving 30-300hz is fairly cheap, a dozen or half-dozen PA woofers will handle that with ease............

8 PA-460's is <$800. That's hella-cheap for that amount of total-cone-area and total-power-handling and total-efficiency!
Would 8 B&C 21's be better? Of course , but it is also approaching 5 figures... (for just a couple more db's.)
Iron Law etc etc.
I am starting to get the point.
1-my subs give me all the low Hz I need the whole house is shaking and you see the doors and curtain moving when running 15hz.
2- the 12 theater solution Speakersmgive me pretty clean listening (especially considering their price)
But even I built sealed enclosure in the wall there are only 8” driver and the enclosure is only 4” deep.
I think this is where my system lack the bass I need between 80Hz and 300Hz

So this is where your idea of 8 PA460 could make sense.
However on the twelve speaker do I really need all of them to have the additional bass?
And it will be definitely be impossible for the 4 ceiling speaker

If what I wrote above is correct the next problem I see is how to implement this?
I can open every speaker and get a connection to the wore with a plug in the wall.
But what about the impedance? If I wired these in parallel I ll be at 4ohms.
But what about the filter? I will need to cut the mid frequency to the PA460 and cut the low to the 8” driver of the in wall.

Last edited by smoke90; 01-05-2020 at 06:43 PM.
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So, what happen when we have bassreflex main speakers? How they mix with ported subwoofers, there are also cancellations?
Cross over the main speakers at or above the main speakers x2F port tuning to avoid port phase delay. Any main speaker with LF <=40Hz will be OK when xover ed at 80Hz.

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post #23 of 26 Old 01-13-2020, 03:33 PM
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from page 5 of that thread

"I was coating the inside of the sub with rubberized undercoating on the joints just to be sure I had a great seal.

Of course it's cold up here in Alberta and not really the best temp for curing undercoating.

had the garage doors open, but I guess the fumes were still making their way to my heater and ....


BOOM!


the fumes exploded and due to the fact I had a piece of board over the large opening all of the blast went out through the port.

Well the nanny was in bed about 60 feet from the explosion and she came out about a minute later yelling that her bed lifted off the ground.

I had some ringing ears due to the shotgun blast sound I had just heard.

Everyone is safe and sound and the fire went out pretty fast."
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post #24 of 26 Old 01-13-2020, 03:44 PM
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Quote:
Originally Posted by smoke90 View Post
I am starting to get the point.
1-my subs give me all the low Hz I need the whole house is shaking and you see the doors and curtain moving when running 15hz.
2- the 12 theater solution Speakersmgive me pretty clean listening (especially considering their price)
But even I built sealed enclosure in the wall there are only 8” driver and the enclosure is only 4” deep.
I think this is where my system lack the bass I need between 80Hz and 300Hz
do you have a rew plot that shows low bass levels in that frequency range?

at any rate, 300hz is well above the subwoofer usages that i've seen, it usually cuts off at 80hz or so.
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post #25 of 26 Old 01-15-2020, 12:40 PM - Thread Starter
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Originally Posted by osv View Post
do you have a rew plot that shows low bass levels in that frequency range?

at any rate, 300hz is well above the subwoofer usages that i've seen, it usually cuts off at 80hz or so.
No I do not and been always travelling since ai posted this
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Keep in mind that the planned Dayton WLS wireless transmitter system has (according to the manual) 32ms of latency.

If the new sub gets positioned close to you (another end table?) this would be mitigated. But the group delay from a ported design might push integration past the delay capabilities of your AVR.
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Sources/processing: stack of stuff that if it isn't vintage now, it will be soon!
Amps: stacks and stacks of old iron
Main speakers: big DIYSG
Surrounds: Bose graveyard
Subs: a bunch
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