Aperiodic Sealed Enclosure

Subwoofery · 11-27-2009, 04:50 AM

Hello,
Making a new thread to revive the Forum... Unless new infos on the BM pops up, not many people post anything

I've been planning a my system change for a while now. But it seems that I won't be able to use the Mag v.4 in a 1.0cuft enclosure.

I read on DIYmobileaudio that one fellow used a sub in an Aperiodic Sealed enclosure. And since he didn't have the equipment, he asked Speaker Works to make in AP mat for his application (based on T/S he provided)
He went from an enclosure that was supposed to be 1.5 sealed to 0.55 AP.

The only problem I see is that I won't be able to seal off the rear wave from the front (like an IB alignment). Can the AP box still be used in that case?

System to go in a Hatchback: active
CD7000 ---- DQS
Sinfoni 50.4 -------> Focal TN52
-------------------> Focal K2P
Audison LRx3.1k ---> Focal K3P
-------------------> 2 x SI Mag v.4

I can only fit up to 1.3cuft sealed (maybe 1.4cuft) for both Mags - been using one only but want to use both now that I'm changing my front amp.

I have a DQS so I have the EQ power to make the freq response smooth and all.

Thanks,
Kelvin

Subwoofery · 11-29-2009, 06:28 PM

Anyone?

Kelvin

Subwoofery · 12-01-2009, 11:17 AM

Seems like the forum is really dead

hobie1dog · 12-01-2009, 09:30 PM

Nick should be popping up anytime now.

Subwoofery · 12-02-2009, 03:44 AM

Quote:

Originally Posted by hobie1dog

Nick should be popping up anytime now.

Hope so

I guess he's really busy getting my BMs ready to be shipped

Kelvin

***Electrodynamic*** · 12-02-2009, 11:07 AM

Sorry for the delayed response.

Yes, I've been busy - not only getting the BM's ready but also with other speaker designs too.

Anyway, you'd actually be surprised at how the Mag v4's will perform in 0.7 ft^3 (your total 1.4 ft^3 enclosure). If you line the walls with fiberglass insulation and then stuff the remainder of the enclosure with polyfill you will receive good results without the use of an aperiodic membrane. However, you can simply use a ScanSpeak aperiodic vent available at Madisound if you want more low-end out of the system. All you have to do is drill a hole and mount the vent to the enclosure. The SS vents are pretty cut and dry - no 'tuning' (changing the stuffing density) necessary.

Subwoofery · 12-02-2009, 12:33 PM

Thanks for the reply... Well I would like to have more low end coz I compared the 2 frequencies in WinIsd: both in 1.4 and both in 2.0cuft - and all I'm getting is more low end without sacrificing high extension

Building a pretty straight forward cubic box, can the AP vent be used on any plane of the box?
What kind of damping material should be used inside the box? Is polyfill better than wool for stuffing the box? The same rule of 1 pound per cuft applies when using any of the two?

Sorry for all the questions but I'm still in the planning stage - have all the equipment and just need to pull the trigger

Thanks,
Kelvin

PS: I forgot to ask... With the SS AP vent, should I isolate the front wave from the back wave like in a real Aperiodic alignment (IB style)?

Thanks

***Electrodynamic*** · 12-02-2009, 04:18 PM

I wouldn't base your decision of what size sealed enclosure to go with based off of the F3 graph that WinISD supplies. When you put a sealed box in a car, that graph means very little. As long as your F3 is around 45 Hz, you'll have plenty of low-end extension all the way down to 20 Hz.

The SS vent can be used on any plane, although we have typically used them on the back side of the enclosure.

As we've always recommended, fiberglass insulation and polyfill is the best combination for stuffing/lining an enclosure. Wool doesn't work as well as polyfill does, and polyfill can be bought at virtually any department store...and it's pretty cheap. The fiberglass insulation (the thin roll of pink insulation) can be purchased at any hardware store or online.

I'm not sure what you're asking in your PS. IB is not the same thing as an Aperiodic membrane. If you build a sealed enclosure, you're isolating the back from from the front wave.

Subwoofery · 12-03-2009, 04:27 AM

Don't worry about the IB, AP thing... I'm thinking out loud :P

Sweet thanks Nick. Now I need to decide whether I'm gonna follow this plan or build a false floor for the subs... Hmm... Hate dilemmas

Thanks for the help,
Kelvin

11-27-2009, 04:50 AM	#1 (permalink)
Subwoofery Member Join Date: Apr 2008 Posts: 88	Aperiodic Sealed Enclosure Hello, Making a new thread to revive the Forum... Unless new infos on the BM pops up, not many people post anything I've been planning a my system change for a while now. But it seems that I won't be able to use the Mag v.4 in a 1.0cuft enclosure. I read on DIYmobileaudio that one fellow used a sub in an Aperiodic Sealed enclosure. And since he didn't have the equipment, he asked Speaker Works to make in AP mat for his application (based on T/S he provided) He went from an enclosure that was supposed to be 1.5 sealed to 0.55 AP. The only problem I see is that I won't be able to seal off the rear wave from the front (like an IB alignment). Can the AP box still be used in that case? System to go in a Hatchback: active CD7000 ---- DQS Sinfoni 50.4 -------> Focal TN52 -------------------> Focal K2P Audison LRx3.1k ---> Focal K3P -------------------> 2 x SI Mag v.4 I can only fit up to 1.3cuft sealed (maybe 1.4cuft) for both Mags - been using one only but want to use both now that I'm changing my front amp. I have a DQS so I have the EQ power to make the freq response smooth and all. Thanks, Kelvin __________________ Eclipse CD7000 ---VDH Integration Hybrid--- Milbert BaM-235ab ---Totem Acoustic Tress--- Focal K3P Highs & Mids ---VDH Jubilee Hybrid--- Audison LRx3.1k ---VDH Clearwater--- Focal K3P Midbasses ---Tara Labs RSC Sub--- Audison LRx3.1k ---VDH Magnum Hybrid--- One (1) Stereo Integrity Mag v.4 D2 sealed in 1.0cuft

11-29-2009, 06:28 PM	#2 (permalink)
Subwoofery Member Join Date: Apr 2008 Posts: 88	Anyone? Kelvin __________________ Eclipse CD7000 ---VDH Integration Hybrid--- Milbert BaM-235ab ---Totem Acoustic Tress--- Focal K3P Highs & Mids ---VDH Jubilee Hybrid--- Audison LRx3.1k ---VDH Clearwater--- Focal K3P Midbasses ---Tara Labs RSC Sub--- Audison LRx3.1k ---VDH Magnum Hybrid--- One (1) Stereo Integrity Mag v.4 D2 sealed in 1.0cuft

12-01-2009, 11:17 AM	#3 (permalink)
Subwoofery Member Join Date: Apr 2008 Posts: 88	Seems like the forum is really dead __________________ Eclipse CD7000 ---VDH Integration Hybrid--- Milbert BaM-235ab ---Totem Acoustic Tress--- Focal K3P Highs & Mids ---VDH Jubilee Hybrid--- Audison LRx3.1k ---VDH Clearwater--- Focal K3P Midbasses ---Tara Labs RSC Sub--- Audison LRx3.1k ---VDH Magnum Hybrid--- One (1) Stereo Integrity Mag v.4 D2 sealed in 1.0cuft

12-01-2009, 09:30 PM	#4 (permalink)
hobie1dog Senior Member Join Date: Mar 2008 Location: Cornelius, NC Posts: 521	Nick should be popping up anytime now. __________________ The bitterness of poor quality remains long after the sweetness of low price has faded. Marry the right person: This one decision will determine 90% of your happiness. Still looking for the speaker that will bruise my chest from Billy Cobham's kick drum.

12-02-2009, 11:07 AM	#6 (permalink)
*Electrodynamic* Stereo Integrity Owner Join Date: Mar 2008 Location: Charlotte, NC Posts: 1,052	Sorry for the delayed response. Yes, I've been busy - not only getting the BM's ready but also with other speaker designs too. Anyway, you'd actually be surprised at how the Mag v4's will perform in 0.7 ft^3 (your total 1.4 ft^3 enclosure). If you line the walls with fiberglass insulation and then stuff the remainder of the enclosure with polyfill you will receive good results without the use of an aperiodic membrane. However, you can simply use a ScanSpeak aperiodic vent available at Madisound if you want more low-end out of the system. All you have to do is drill a hole and mount the vent to the enclosure. The SS vents are pretty cut and dry - no 'tuning' (changing the stuffing density) necessary. __________________ Electrodynamic Don't install suckage! Power handling is not a power requirement.

12-02-2009, 12:33 PM	#7 (permalink)
Subwoofery Member Join Date: Apr 2008 Posts: 88	Thanks for the reply... Well I would like to have more low end coz I compared the 2 frequencies in WinIsd: both in 1.4 and both in 2.0cuft - and all I'm getting is more low end without sacrificing high extension Building a pretty straight forward cubic box, can the AP vent be used on any plane of the box? What kind of damping material should be used inside the box? Is polyfill better than wool for stuffing the box? The same rule of 1 pound per cuft applies when using any of the two? Sorry for all the questions but I'm still in the planning stage - have all the equipment and just need to pull the trigger Thanks, Kelvin PS: I forgot to ask... With the SS AP vent, should I isolate the front wave from the back wave like in a real Aperiodic alignment (IB style)? Thanks __________________ Eclipse CD7000 ---VDH Integration Hybrid--- Milbert BaM-235ab ---Totem Acoustic Tress--- Focal K3P Highs & Mids ---VDH Jubilee Hybrid--- Audison LRx3.1k ---VDH Clearwater--- Focal K3P Midbasses ---Tara Labs RSC Sub--- Audison LRx3.1k ---VDH Magnum Hybrid--- One (1) Stereo Integrity Mag v.4 D2 sealed in 1.0cuft Last edited by Subwoofery; 12-02-2009 at 12:43 PM.

12-02-2009, 04:18 PM	#8 (permalink)
*Electrodynamic* Stereo Integrity Owner Join Date: Mar 2008 Location: Charlotte, NC Posts: 1,052	I wouldn't base your decision of what size sealed enclosure to go with based off of the F3 graph that WinISD supplies. When you put a sealed box in a car, that graph means very little. As long as your F3 is around 45 Hz, you'll have plenty of low-end extension all the way down to 20 Hz. The SS vent can be used on any plane, although we have typically used them on the back side of the enclosure. As we've always recommended, fiberglass insulation and polyfill is the best combination for stuffing/lining an enclosure. Wool doesn't work as well as polyfill does, and polyfill can be bought at virtually any department store...and it's pretty cheap. The fiberglass insulation (the thin roll of pink insulation) can be purchased at any hardware store or online. I'm not sure what you're asking in your PS. IB is not the same thing as an Aperiodic membrane. If you build a sealed enclosure, you're isolating the back from from the front wave. __________________ Electrodynamic Don't install suckage! Power handling is not a power requirement.

12-03-2009, 04:27 AM	#9 (permalink)
Subwoofery Member Join Date: Apr 2008 Posts: 88	Don't worry about the IB, AP thing... I'm thinking out loud :P Sweet thanks Nick. Now I need to decide whether I'm gonna follow this plan or build a false floor for the subs... Hmm... Hate dilemmas Thanks for the help, Kelvin __________________ Eclipse CD7000 ---VDH Integration Hybrid--- Milbert BaM-235ab ---Totem Acoustic Tress--- Focal K3P Highs & Mids ---VDH Jubilee Hybrid--- Audison LRx3.1k ---VDH Clearwater--- Focal K3P Midbasses ---Tara Labs RSC Sub--- Audison LRx3.1k ---VDH Magnum Hybrid--- One (1) Stereo Integrity Mag v.4 D2 sealed in 1.0cuft

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