# Stereo Integrity SQL-12 D2 - sealed vs ported vs IB + enclosure sizes for SQ(L) setup



## hella356 (Dec 11, 2016)

I'm putting a Stereo Integrity SQL-12 D2 in a prefab sealed 1.0cf box temporarily since I don't have time to do anything else before I go on a long road trip. Amp is Sundown Audio SFB-1000D and will be run at 1 Ohm in a 2006 Hyundai Sonata trunk, playing mostly rock & roll with some heavy metal, rap, classical, etc. It will replace an Image Dynamics ID10 in 1.0 sealed. MiniDSP Dirac DSP is in the system. SQ is the highest priority, but getting good impact/volume should be a very welcome upgrade from the ID10. I've been planning to give a go with a sealed fiberglass side enclosure to fill in unused trunk space, although I'm open to anything. I'm thinking a ported box will be unlikely due to size, but if the performance is worth it, I'd consider that. Apparently this driver does well in IB - this would be better in terms of space than ported, I think, but would also lose the pass-through capability of the rear seats.

I'll soon be finding out how well it does in 1.0cf, albeit in a fairly cheap box - this is the upper limit of what SI suggests for sealed. All things being equal, I'd prefer the smallest cabinet size that performs well. SI's recommendation for vented is 1.5cf - not gigantic, but still pretty big. Any suggestions?


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## chrisp2493 (Apr 18, 2021)

I’ve got the same sub and was planning on a 1 ft3 sealed box. But now I keep seeing infinite baffle come up and I’m slightly interested in trying that out. Wasn’t sure if this sub would work for that or not


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## ckirocz28 (Nov 29, 2017)

hella356 said:


> I'm putting a Stereo Integrity SQL-12 D2 in a prefab sealed 1.0cf box temporarily since I don't have time to do anything else before I go on a long road trip. Amp is Sundown Audio SFB-1000D and will be run at 1 Ohm in a 2006 Hyundai Sonata trunk, playing mostly rock & roll with some heavy metal, rap, classical, etc. It will replace an Image Dynamics ID10 in 1.0 sealed. MiniDSP Dirac DSP is in the system. SQ is the highest priority, but getting good impact/volume should be a very welcome upgrade from the ID10. I've been planning to give a go with a sealed fiberglass side enclosure to fill in unused trunk space, although I'm open to anything. I'm thinking a ported box will be unlikely due to size, but if the performance is worth it, I'd consider that. Apparently this driver does well in IB - this would be better in terms of space than ported, I think, but would also lose the pass-through capability of the rear seats.
> 
> I'll soon be finding out how well it does in 1.0cf, albeit in a fairly cheap box - this is the upper limit of what SI suggests for sealed. All things being equal, I'd prefer the smallest cabinet size that performs well. SI's recommendation for vented is 1.5cf - not gigantic, but still pretty big. Any suggestions?


Personally, I would keep it running sealed.


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## daloudin (Nov 2, 2020)

The optimum ported box for the SQL12 is 1.25 to about 1.4 and tuned for 24-25 Hz but the problem is figuring out how to build such a small ported box tuned that low. You need around 20-25 sqin of port area at 1kW and that ends up being about 6 FEET long to hit 24 Hz so you have to do a labyrinth port and the total box size gets big due to the port volume. I've created a few designs in Sketchup but most people forget the ported box once they've heard the SQL in a proper sealed enclosure. 

Mine started out as a Denovo 1 cuft knock down from Parts Express that had extra bracing added to get the net volume down to 0.7 cuft on Taramps Smart 3K and while it will handle that power I rarely turn it up full volume. 

If you make your own box from 3/4" MDF it ends up only being 14"x14"x10" external dimensions to get a net internal volume of 0.62 cuft and there's literally no room left for bracing. 

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## hella356 (Dec 11, 2016)

Thanks! Any opinions about the size of a sealed box? SI says .65 to 1.0 cubes.


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## hella356 (Dec 11, 2016)

daloudin said:


> The optimum ported box for the SQL12 is 1.25 to about 1.4 and tuned for 24-25 Hz but the problem is figuring out how to build such a small ported box tuned that low. You need around 20-25 sqin of port area at 1kW and that ends up being about 6 FEET long to hit 24 Hz so you have to do a labyrinth port and the total box size gets big due to the port volume. I've created a few designs in Sketchup but most people forget the ported box once they've heard the SQL in a proper sealed enclosure.
> 
> Mine started out as a Denovo 1 cuft knock down from Parts Express that had extra bracing added to get the net volume down to 0.7 cuft on Taramps Smart 3K and while it will handle that power I rarely turn it up full volume.
> 
> ...


Wow, that pretty much takes ported out of the equation. The temporary prefab has no bracing, but I've been assuming if I build a new sealed box, a driver this potent will require a beefier, braced construction. But it sounds like you're saying a box towards the smaller end of the range is preferable in-car? I suppose I could add bracing to the prefab, which would subtract some volume.


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## daloudin (Nov 2, 2020)

Prefab box joints (edges) are the weak link - if you stay in the 0.6-0.7 range the extra Qtc means it will handle even more power and create more pressure. For this kind of pressure the edges really need to be dadoed and/or have additional material added in the corners and a double thick front baffle to be as inert as possible. But it all really depends on how hard you plan to run it as a daily. You can add bricks or 2x4s to your prefab box to test different volumes before you build a final.

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## pw91686 (Apr 1, 2015)

the 1 cu ft enclosure should be fine for that driver considering total volume after displacement of the driver. those drivers work best sealed, so i would run it sealed. 
if IB is best for you, then get rid of the sql and buy a driver specifically designed for IB for better results.


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## hella356 (Dec 11, 2016)

Great stuff, guys. Just the kind of input I was hoping for. For sure when I build the final box, it will be far better braced than the prefab. And good tip on placing wood/bricks to test different volumes. That would make me far more confident about building the correct sized box.


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## daloudin (Nov 2, 2020)

pw91686 said:


> the 1 cu ft enclosure should be fine for that driver considering total volume after displacement of the driver. those drivers work best sealed, so i would run it sealed.
> if IB is best for you, then get rid of the sql and buy a driver specifically designed for IB for better results.


Agreed - The SQL12 has a displacement of 0.15 so likesaid you should already be at 0.85 so it wouldn't take much to get down another couple of tenths. Also, your particular installation may benefit more from the slightly extended response from a bigger box without adding more power so the testing may show you that the box you have is fine. 

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## Jroo (May 24, 2006)

hella356 said:


> Wow, that pretty much takes ported out of the equation. The temporary prefab has no bracing, but I've been assuming if I build a new sealed box, a driver this potent will require a beefier, braced construction. But it sounds like you're saying a box towards the smaller end of the range is preferable in-car? I suppose I could add bracing to the prefab, which would subtract some volume.


Wouldnt this be a perfect application of passive radiators? With the size of the box and low tuning, A pair of passive radiators on either side should work. I have never personally used a PR, but have seen them in use. I know we have several on the forum that have experience, but this sounds like a great application.


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## hella356 (Dec 11, 2016)

daloudin said:


> Agreed - The SQL12 has a displacement of 0.15 so likesaid you should already be at 0.85 so it wouldn't take much to get down another couple of tenths. Also, your particular installation may benefit more from the slightly extended response from a bigger box without adding more power so the testing may show you that the box you have is fine.


I've never been quite sure if the enclosure size recommendations by manufacturers take driver displacement into consideration or not. This particular driver has .65-1.0 recommended; is it implied that this is minus the displacement? Prefab boxes have a specific cubic foot volume, but if one purchased or built a box with a .65 gross volume, it would actually have a net volume of .50 with this driver, which is out of the recommended range. And if I wanted a net volume of 1.0, the gross volume would need to be 1.15. But I could also see this interpreted as "put it in a prefab box sized at .65-1.0". I figure a true test of how the sub works in my car with a range of volumes would mean starting with a 1.15, then filling in space until a sweet spot is reached. In my situation, I suppose could also add poly fill to replicate a larger box. Thanks for the pointers - short term, I just need a box to enjoy on my trip, but the prefab is also a great opportunity to zero in on the ideal size to build its replacement.


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## hella356 (Dec 11, 2016)

Jroo said:


> Wouldnt this be a perfect application of passive radiators? With the size of the box and low tuning, A pair of passive radiators on either side should work. I have never personally used a PR, but have seen them in use. I know we have several on the forum that have experience, but this sounds like a great application.


Oh, great - throw a monkey wrench into my plans!  That is an interesting thought. I have no experience with PRs, and since my dream scenario, long-term, is the smallest possible fiberglass box in the unused space in a rear corner between the wheel well and rear of trunk, I don't see who PRs could be used in that situation. However, if that seems unfeasible (and I do have a friend looking to make a sub box for his truck) I'll have to research PRs for that.


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## DavidRam (Nov 2, 2014)

I just finished a box for a SQL12 - about 1.2 cuft sealed. Haven't installed, tuned and listened yet, though, so I guess this post is worthless! Lol

Approx OD
32 x 14.5 x 8


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## hella356 (Dec 11, 2016)

Haha, worthless post, but very impressive box!


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## DavidRam (Nov 2, 2014)

Lol! Thanks!

I'll update with listening impressions, asap...


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## miniSQ (Aug 4, 2009)

Having played with the big brother to the SQL-12 ( the RM-12). I think you will be most happy with a small sealed box that is well built.


hella356 said:


> I've never been quite sure if the enclosure size recommendations by manufacturers take driver displacement into consideration or not. This particular driver has .65-1.0 recommended; is it implied that this is minus the displacement? Prefab boxes have a specific cubic foot volume, but if one purchased or built a box with a .65 gross volume, it would actually have a net volume of .50 with this driver, which is out of the recommended range. And if I wanted a net volume of 1.0, the gross volume would need to be 1.15. But I could also see this interpreted as "put it in a prefab box sized at .65-1.0". I figure a true test of how the sub works in my car with a range of volumes would mean starting with a 1.15, then filling in space until a sweet spot is reached. In my situation, I suppose could also add poly fill to replicate a larger box. Thanks for the pointers - short term, I just need a box to enjoy on my trip, but the prefab is also a great opportunity to zero in on the ideal size to build its replacement.


Its not always the same for all companies. But i believe SI, AF and JL all take into consideration the displacement of the driver when recommending sizes so you can consider those companies Gross sizes. But always best to check before cutting wood.


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## hella356 (Dec 11, 2016)

miniSQ said:


> Having played with the big brother to the SQL-12 ( the RM-12). I think you will be most happy with a small sealed box that is well built.
> 
> Its not always the same for all companies. But i believe SI, AF and JL all take into consideration the displacement of the driver when recommending sizes so you can consider those companies Gross sizes. But always best to check before cutting wood.


Thank you. After thinking about it more, it makes sense that companies like Pioneer, Kenwood, Kicker, and such would be more likely to assume their sub drivers would go in a prefab, whereas companies like you listed would probably assume more accurate, custom boxes built specifically for their drivers. Initially, I'm going to install in stock, then add blocks to lower air volume. If that improves things, I'll install actual bracing of similar volume. If smaller volume makes it worse, I'll remove blocks & add poly fill to test the opposite direction, but hopefully adding bracing gets the air volume just right.


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## Mad Scientist (Feb 12, 2017)

Since porting the SQL 12 and 15 are a nightmare, I'd be curious to see how they perform with a passive radiator. PSI offers high excursion PR's, and they seem to be a good trade off for people who don't have the real estate or aren't willing to give up the real estate a ported design would require. 

Has anyone designed or built a PR'd SQL 12 or 15 yet?


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## maybebigfootisblurr (Nov 4, 2011)

Jroo said:


> Wouldnt this be a perfect application of passive radiators? With the size of the box and low tuning, A pair of passive radiators on either side should work. I have never personally used a PR, but have seen them in use. I know we have several on the forum that have experience, but this sounds like a great application.


Legend has it that actually spelling out PR three times in one post, will summon The Holmz... that was a close one!


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## miniSQ (Aug 4, 2009)

I imagine it would get tough to fit PR's on such strong drivers. I think you might need a pair of 15's on the SQL12 if you plan to hammer it with power. Maybe 2 12's, but still.


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## daloudin (Nov 2, 2020)

Indeed - finding PR's that have the Sd and excursion to keep up is the 1st hurdle. The second hurdle is that the box for the 12 with 2 x15 PR's is difficult to build since it really only needs to be about 1.3 cuft net internal and that doesn't leave much in the way of options for cabinet construction. For me, given the cost and how small the sealed enclosure can be and how cheap Watts are I'd rather but another active driver than do PR's but I do love a good sealed sub. 

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## daloudin (Nov 2, 2020)

Fug - now I can't stop thinking about it... models to come shortly! LOL


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## hella356 (Dec 11, 2016)

Yeah, I like the sound, simplicity, and size of sealed subs, but despite PRs not looking like a viable option for my setup, I am curious about whether it's even possible.

Initially it was indicated that I'd be receiving the SQL tomorrow, but looks like it won't be arriving until Thursday. Feel like a kid being told Christmas got pushed back a week! Got an email from SI that the carbon fiber dust cap slows down the process, plus gas shortages and such are slowing things down. Cant' be helped, and glad they sent an update, but the wait is killing me! I have little doubt it will be worth the wait, though.


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## daloudin (Nov 2, 2020)

So the 15" High Excursion PSI Sub works mathematically for the tuning = 1.2 cuft box with 900g of added mass for an Fs of 8.3 Hz and neither the active nor the passive hit's mechanical limits with 3kW of power *BUTT *(you knew that was coming...) it's $265 for the PR (almost another active) AND it has a 14.8" bolt diameter and a 7" mounting depth (NOT accounting for movement of the added weights on the back) so it's nearly as deep as the SQL so you'd have to make a box with a minimum of about 16" of mounting depth in order to mount them back-to-back and even with tapered sides I don't see it being possible - maybe an hourglass enclosure? Anybody feeling froggy to make one of the tightest enclosures on planet earth?

Sub Box Pro Model


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## miniSQ (Aug 4, 2009)

hella356 said:


> Yeah, I like the sound, simplicity, and size of sealed subs, but despite PRs not looking like a viable option for my setup, I am curious about whether it's even possible.
> 
> Initially it was indicated that I'd be receiving the SQL tomorrow, but looks like it won't be arriving until Thursday. Feel like a kid being told Christmas got pushed back a week! Got an email from SI that the carbon fiber dust cap slows down the process, plus gas shortages and such are slowing things down. Cant' be helped, and glad they sent an update, but the wait is killing me! I have little doubt it will be worth the wait, though.


i have no need for it, but i am so tempted to snag a 12 with the carbon dustcap.


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## miniSQ (Aug 4, 2009)

daloudin said:


> So the 15" High Excursion PSI Sub works mathematically for the tuning = 1.2 cuft box with 900g of added mass for an Fs of 8.3 Hz and neither the active nor the passive hit's mechanical limits with 3kW of power *BUTT *(you knew that was coming...) it's $265 for the PR (almost another active) AND it has a 14.8" bolt diameter and a 7" mounting depth (NOT accounting for movement of the added weights on the back) so it's nearly as deep as the SQL so you'd have to make a box with a minimum of about 16" of mounting depth in order to mount them back-to-back and even with tapered sides I don't see it being possible - maybe an hourglass enclosure? Anybody feeling froggy to make one of the tightest enclosures on planet earth?
> 
> Sub Box Pro Model
> 
> View attachment 301488


time to start a gofundme for @Holmz


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## hella356 (Dec 11, 2016)

miniSQ said:


> i have no need for it, but i am so tempted to snag a 12 with the carbon dustcap.


It does look pretty cool, and was a free upgrade, but had I known it would set things back a couple days, I would have skipped it. I wouldn't think it would really affect performance much, although I have no idea if that's true.


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## miniSQ (Aug 4, 2009)

hella356 said:


> It does look pretty cool, and was a free upgrade, but had I known it would set things back a couple days, I would have skipped it. I wouldn't think it would really affect performance much, although I have no idea if that's true.


I don't think it would matter sound wise, but waiting a week for that coolness is worth it. Just take deep patient breaths. LOL.


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## hella356 (Dec 11, 2016)

Haha! Yes, that's the plan. Ordinarily I wouldn't mind the delay, but it has postponed a 2 week road trip around northern California I've been itching to go on. Worth it, I expect, though. I don't blame SI - these things happen.


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## ckirocz28 (Nov 29, 2017)

hella356 said:


> It does look pretty cool, and was a free upgrade, but had I known it would set things back a couple days, I would have skipped it. I wouldn't think it would really affect performance much, although I have no idea if that's true.


It's purely for looks. Carbon fiber is heavier than paper or plastic dust cones, but not enough to affect performance. They just look awesome.


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## Mad Scientist (Feb 12, 2017)

daloudin said:


> So the 15" High Excursion PSI Sub works mathematically for the tuning = 1.2 cuft box with 900g of added mass for an Fs of 8.3 Hz and neither the active nor the passive hit's mechanical limits with 3kW of power *BUTT *(you knew that was coming...) it's $265 for the PR (almost another active) AND it has a 14.8" bolt diameter and a 7" mounting depth (NOT accounting for movement of the added weights on the back) so it's nearly as deep as the SQL so you'd have to make a box with a minimum of about 16" of mounting depth in order to mount them back-to-back and even with tapered sides I don't see it being possible - maybe an hourglass enclosure? Anybody feeling froggy to make one of the tightest enclosures on planet earth?
> 
> Sub Box Pro Model


To reduce the depth from being 16", you could do an inverted mounting on the active subs, or PR's, or both to meet a very small box requirement.


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## ckirocz28 (Nov 29, 2017)

daloudin said:


> So the 15" High Excursion PSI Sub works mathematically for the tuning = 1.2 cuft box with 900g of added mass for an Fs of 8.3 Hz and neither the active nor the passive hit's mechanical limits with 3kW of power *BUTT *(you knew that was coming...) it's $265 for the PR (almost another active) AND it has a 14.8" bolt diameter and a 7" mounting depth (NOT accounting for movement of the added weights on the back) so it's nearly as deep as the SQL so you'd have to make a box with a minimum of about 16" of mounting depth in order to mount them back-to-back and even with tapered sides I don't see it being possible - maybe an hourglass enclosure? Anybody feeling froggy to make one of the tightest enclosures on planet earth?
> 
> Sub Box Pro Model
> 
> View attachment 301488


I don't know what the depth is on these, but they have the excursion needed. $170 for 2.








SHOP | css-audio







www.css-audio.com


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## daloudin (Nov 2, 2020)

ckirocz28 said:


> I don't know what the depth is on these, but they have the excursion needed. $170 for 2.
> 
> 
> 
> ...


There u go 16" cube with the active on the front and one of these inverted on each side. Where there a will there's a way! 

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## ckirocz28 (Nov 29, 2017)

daloudin said:


> There u go 16" cube with the active on the front and one of these inverted on each side. Where there a will there's a way!
> 
> Sent from my SM-G965U using Tapatalk


The flat pack they sell with 1 sub and 2 pr's is an 18.5 inch cube, and the magnet on those subs is 9.5 inches wide, so the pr's can't be much more than 4.5 inches deep each.


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## lashlee (Aug 16, 2007)

I just snagged one of the SPL-15's with the carbon dust cap for my next install so I'm interested to see how this plays out. I don't have the space for a ported enclosure so I'll stick with the sealed dimensions that SI recommends...even with about 1800 watts going to it I'm sure it's gonna make some noise!


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## hella356 (Dec 11, 2016)

Interesting that they list the 12 from .65 to 1.0, but only list 2.0 for the 15.


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## LaserSVT (Feb 1, 2009)

I can not speak to the sound/output of a ported SQL12 but can tell you in a 1.07 CF sealed box with 1100 watts that they perform excellent. They have amazing extension below 20hz and have a very tight attack and decay in a sealed box. They stay very true to the music and are amazingly loud for any sub much less an SQ specific sub. I will be running a pair in my other vehicle with 850 on each sub in a 1.1 CF sealed box and expect great things. These numbers are before driver displacement.
On the car where one has 1100 watts it is in the trunk of a Jaguar and their trunks are VERY well isolated from the cabin yet the sub still sounded great. In the other build its a truck and they will be sitting under the rear seat in the cabin with me so I am sure they will be able to get much louder than I can handle. I am using the SIQ amps and they are impressively powerful!


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## hella356 (Dec 11, 2016)

Newb question, but what is the proper wiring to run a D2 SQL-12 at 1 Ohm?


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## maybebigfootisblurr (Nov 4, 2011)

R1 x R2 / R1 + R2 for parallel

R1 + R2 for series

Therefore, your D2 in parallel will present a 1 ohm load. To be clear, this is not an SI SQL specific method, it's Ohm's Law.


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## Holmz (Jul 12, 2017)

hella356 said:


> Newb question, but what is the proper wiring to run a D2 SQL-12 at 1 Ohm?


Watts = V*I
V=IR so I=V/R

So we can then get to this:
W = V*V/R 
(Using the algebra.)

Hence V is over 30V, and I (current/amperes) is also a bit over 30A

So now find the wire size needed for 30+ amperes, and the acceptable voltage drop.


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## hella356 (Dec 11, 2016)

maybebigfootisblurr said:


> R1 x R2 / R1 + R2 for parallel
> 
> R1 + R2 for series


+ from amp to + on sub
Jumper from + to + 

- from amp to - on sub
Jumper from - to -

That correct?

Using 12 gauge speaker wire, figure this should be sufficient.


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## maybebigfootisblurr (Nov 4, 2011)

hella356 said:


> + from amp to + on sub
> Jumper from + to +
> 
> - from amp to - on sub
> ...


That is correct for parallel configuration.
Wire size... depends on how much power/length of run.


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## hella356 (Dec 11, 2016)

maybebigfootisblurr said:


> That is correct for parallel configuration.
> Wire size... depends on how much power/length of run.


Thanks! I thought that was the wire config, but always good to get confirmation by more knowledgeable people. The 12 gauge is the short run in the box + about 6 feet from amp to box. That seem OK?


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## hella356 (Dec 11, 2016)

Without any real break-in time, still playing with DSP setup, and in a lowly prefab box (1.0 sealed), this SQL-12 is kicking ass! Pretty much exactly what I was hoping for to replace the ID10 I was using - at least as good in terms of being articulate and tuneful, but with substantially more powerful deep bass. And not feeling tentative about getting high output like I was with the ID10, which replaced another ID10 I had killed. Considering that I'm definitely not extracting all of its potential yet, very excited to hear what it does at closer to max performance.


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## JI808 (Nov 20, 2013)

You guys may think I'm crazy, but I built an enclosure for a SQL-12 that's 2.25ft^3 tuned to 22Hz with 19 1/2 sq in of port area.

I slammed this together during an overnight thrash session on a guy's vehicle to get him to a competition. Was a complete rebuild of the install. 

You can see the Term-Pro chart, the construction, and the end result. 

The port is 13" tall and 1 1/2" wide with a flare at the baffle exit to reduce turbulence.

The 3rd image shows the JL Tun software. You can see that there's a 70Hz LR4 on channels 7/8 and there's no EQ applied to the sub.

Just below the Tun window you see the response (six mic average at the listening position) in SysTune. It's damn near flat. Like a 2dB deviation at 40-ish.

Port noise wasn't an issue.

This sub will play anything in this enclosure. The 8Hz note in Bass I Love you was moving the guy's entire liftgate when the sub was powered with a DD Audio M1d. We measured something like 400 Watts that the sub was seeing.

People have a hard time believing they're listening to a single 12 and they all comment on how clean/effortless the bass is.


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## hella356 (Dec 11, 2016)

My cheap prefab box is a placeholder until I build a fiberglass stealth enclosure to regain usable trunk space, so opposite direction of your box, but _dang_ that's impressive.


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## txkawboi (Jul 17, 2015)

If you're an ole old basshead from the 80s & 90s like I am _clears thote lol_, then this is where it's at! 4.7 cuft tuned to 22 Hz with plenty power has finally gotten me where I wanna be in this vehicle! JI808, you've got a winner my brotha. Thanx so much for sharing your build & the data to back it up. These SQLs are REEEEDICULOUS! I admit that I doubted they could match the output of my son's RM-12s (I passed them down) but I think they're right there. Thanx again!


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## Dsmcolt (Dec 21, 2020)

Would one of these be enough pr for an sql 15 on 1500ish watts?






PUMP-12 - Earthquake Sound Corp.


Earthquake Sound is the manufacturer of speakers, subwoofers, and audio accessories for home theater and mobile audio sound systems. Proudly engineered in Hayward, California




www.earthquakesound.com


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## daloudin (Nov 2, 2020)

Dsmcolt said:


> Would one of these be enough pr for an sql 15 on 1500ish watts?
> 
> 
> 
> ...


No way to know. They don't publish enough specifications to model the pump. They say it has 226 in^2 of piston area but that's HUGE compared to most 12" PRs and with no xmax, mms, vas or Qts specified the only way to find out is to go trial and error. 

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## Dsmcolt (Dec 21, 2020)

daloudin said:


> No way to know. They don't publish enough specifications to model the pump. They say it has 226 in^2 of piston area but that's HUGE compared to most 12" PRs and with no xmax, mms, vas or Qts specified the only way to find out is to go trial and error.
> 
> Sent from my SM-G965U using Tapatalk


 Just the person i was hoping would come back and answer. Well it is 2 pr and They sure look the same as the slaps 12 pr's. Do you think it would be worth my time, worst case they need some more weight.


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## daloudin (Nov 2, 2020)

There's 2 issues - one is the tuning point which you can change by adding weight as you mentioned. The other is mechanical. 

Vd is volume displacement and if the Sd × xmax of the SQL is more than the pump then it will exceed mechanical limits and possibly create audible noise and/or damage. (There's also inertia to consider which is also variable with additional mass but you get the idea.) The only way to prevent that is by adding a 2nd pump. 

Lemme see what happens using the regular PR as dual to one SQL15.

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## daloudin (Nov 2, 2020)

This will be full of caveats.

1. The pump is not predrilled for added weight like the regular PR comes. You will HAVE to add weight in order to get the tuning right as without added weight the Fs is WAY too high and becomes a mess. THIS IS THE MOST IMPORTANT - Cause if you're not comfortable drilling holes in the diaphragms of your brand new Pump12 then stop right here...

2. This is using the SLAPS M12 specifications as that's all they publish.

3. Took the quoted 4" of xmax and assumed that was total so one way is modeled as 2" xmax - take that for what you will but 4" of xmax is HUGE.

With all of that and 1500 Watts Max into the SQL15 the Pump12 is getting close to the limit of it's mechanical excursion.

Box size works from 2 cuft net with 400g of weight per diaphragm (800g total and I'm thinking you'd have to be very careful with mounting depth of the weight as the two PRs are moving towards each other) to 3cuft net with 300g per diaphragm and 4cuft net with 200g of weight. The bigger the box the lower the F3 but not by much.

15Hz Infrasonic LR24 on all 3...


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## Dsmcolt (Dec 21, 2020)

Thank you for all that i did find this on there site ive never seen before, came up with numbers real close to what you suggested would be needed



Subwoofer design with SLAPS passive radiator




I do have an email in to earthquake to see if they will give anymore info.


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## daloudin (Nov 2, 2020)

Yes - I've seen that before. 

Just not sure that two 12s connected by a shared manifold will behave the same as two separate PRs mounted on the baffle. Would be interesting to see though... those two radiators slamming back and forth 4" each pushing air out that one port - hard to believe there won't be some kind of turbulence. But I say that to say this; that the shared manifold behaves as a tuned port for the PRs so that has to affect the tuning frequency thus the models above are merely an exercise and would not be indicative of the actual weights needed. 

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