# Dual 10" vs a single 12" subs for SQ



## ZAKOH (Nov 26, 2010)

I have been contemplating upgrading my car to a dual 12 inch sealed sub setup, but alas I am afraid I am going to have trouble fitting such an enclosure in my trunk. However, a dual sealed enclosure with 10 inch woofers will fit (anything 26 inch wide or less, will fit). 

So, I am tentatively deciding between a mid-level 12 inch SQ subwoofer such as RE Audio SE/X in a sealed box vs two entry level subs 10inch, such as RE Audio SRX or something similar. I will have roughly 500-600 watt RMS channel to power them. 

Which of these two setups will give better SQ? The pros of dual 10" setup it seems like it will have bigger cone area, so it will need less excursion to play. At the same time, the dual 10" setup does not have a whole lot more surface area compared to a single 12", but it does add more weight and take up more trunk space.


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## Chaos (Oct 27, 2005)

It sounds as if a single high-powered 12" that has been consistently noted to perform well in sealed enclosures would be the best solution for your application. Perhaps something like a JL 12W6? (A few weeks ago I would have said an IDMax would be perfect, but now - not so much)


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## FG79 (Jun 30, 2008)

Dual 10s.


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## Angrywhopper (Jan 20, 2010)

Single 12.


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## St. Dark (Mar 19, 2008)

I would compare apples to apples: if you like a 12", then the 10" version of that same sub will (usually) perform very similar other than less output and maybe a tad higher rolloff. (as in with XtremeRevolution's example of the IDQ10's; an IDQ12 or even the 15 of the same gen were engineered to sound essentially the same)

When you shift from 1 of x to 2 of y, that changes things a bit. There, you have to evaluate if you like the 10" in question. If you do, then great, and a pair of them will move a bit more air. If you don't....you don't.


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## sqshoestring (Jun 19, 2007)

I think it depends on the sound you want, as tuning of 12 and 10 will typically be different (not always).

I'll give a X2 on multiple subs, always what I try to do. Another thing about large subs is they don't need to make the xmax of a smaller sub, so for the same SPL all your distortions should be less assuming similar quality driver is used. My pair of 15s hardly move at plenty of output for a good SQ listen.


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## Lance_S (Feb 11, 2009)

I believe the cone area of a single 12 is equivalent to two 10's. The output is similar as well. I currently run a single 12 sealed in a 4th order enclosure with about 1 cubic foot of space. The box is small, light weight (relatively speaking), effecient and sounds great. 

Sometimes you wish you could A/B compare them on the spot don't you?


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## sqshoestring (Jun 19, 2007)

Lance_S said:


> Sometimes you wish you could A/B compare them on the spot don't you?


Yes, but odds are slim of having similar tuning/driver/etc. Actually the last subs I ran the 10s sounded better, but I have no doubt the 12s were not tuned as I like them. But my IB 15s are maybe 1,000% better than either.


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## quietfly (Mar 23, 2011)

just some food for thought 2 kicker soloclassic 12's will fit in a 26 inch space the *OUTSIDE* measurements of each cube is 13x13x13. 

then you'd have 2 12's


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## XtremeRevolution (Dec 3, 2010)

Lance_S said:


> I believe the cone area of a single 12 is equivalent to two 10's. The output is similar as well. I currently run a single 12 sealed in a 4th order enclosure with about 1 cubic foot of space. The box is small, light weight (relatively speaking), effecient and sounds great.
> 
> Sometimes you wish you could A/B compare them on the spot don't you?


I don't mean to be rude, but try doing some math. 

When working with circles, the area of a two 10" circles is 157 square inches. The area of one 12" circle is 113 square inches. Most subs will publish their actual cone surface area for you to compare. The area of a 15" circle is 176.71 square inches.


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## sqshoestring (Jun 19, 2007)

I usually take the volume I can make the box, then I go to the model and try for the curve I want....what ever looks better I get that. To me response is more important. On the other side a larger sub might have a lower Fs, if you can fit it, it may dig lower.


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## fearturtle03 (Apr 5, 2011)

2 10's


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## Bayboy (Dec 29, 2010)

Before you can evenly compare different size subs, individual characteristics must be looked at. Compliance and actual amount of air moved in a single stroke can make a world of difference between what you choose. Plotting on a extensive software or some deep calculations will let you see the difference, but THD is another aspect. I'd say those options could be apples to oranges. IMO multiple subs always present less distortion at upper limits.


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## Bayboy (Dec 29, 2010)

Yeah it's not so easy making a comparison on paper. You've got to pretty much evaluate the driver hands on because there is much more than specs and graphs..... Personally I have always favored a pair of 10" out of every setup that I've had. Though they may not have the most output, SQ wise they were easier to blend with the front stage and more easier to manipulate without using overly large enclosures to do so.


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## subwoofery (Nov 9, 2008)

You need to think first about how much space you're willing to sacrifice. 
When you have a volume (cuft) then you can plot whichever/whatever sub and multiple subs to get a decent curve. 

Not really the other way around IMO as _sqshoestring_ stated. 

Kelvin


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## azluda87 (Apr 8, 2011)

I vote 10


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## ZAKOH (Nov 26, 2010)

subwoofery said:


> You need to think first about how much space you're willing to sacrifice.
> When you have a volume (cuft) then you can plot whichever/whatever sub and multiple subs to get a decent curve.
> 
> Not really the other way around IMO as _sqshoestring_ stated.
> ...



Well, I can sacrifice whatever amount of space it takes to run a sealed 12 inch subwoofer. So between 1 and 2ft^3. For dual 10 inch subwoofers, I'd buy a prefabricated dual chamber box like this one:

Sonic Sub Boxes 2SL10-1.5-BLACK (2sl1015-black) Dual 10" Sealed

Which has about 0.75ft^3 per chamber.


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## sqshoestring (Jun 19, 2007)

subwoofery said:


> You need to think first about how much space you're willing to sacrifice.
> When you have a volume (cuft) then you can plot whichever/whatever sub and multiple subs to get a decent curve.
> 
> Not really the other way around IMO as _sqshoestring_ stated.
> ...


That is what I thought I wrote, maybe it was not clear. I take the largest box acceptable to install then try to put sub(s) in it that work like I want.

You could make a ported single 12 with more xmax and get pretty low, or run pair of 10 sealed in same volume of space....they would sound different, but some people would like one some the other...that is where a curve helps you. I like the lower one the ported 12, maybe with lots of cabin gain the 10s would be better.

Only way I know of figuring it out blind is to put a temp sub in the car and model it. Tune that sub with an EQ, then take your EQ settings and add that to that model. The new curve should then include the cabin gain and your preferences, and while not precision it should give you an ideal estimated model of your new sub setup (that you need to find/design/build in the allocated space)

I pretty much ignore factory recommendations and build a box to work like I want. Yes once in a while its not possible in the room I have to work with.


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## D1g1tal V3n0m (Dec 24, 2008)

ZAKOH said:


> I have been contemplating upgrading my car to a dual 12 inch sealed sub setup, but alas I am afraid I am going to have trouble fitting such an enclosure in my trunk. However, a dual sealed enclosure with 10 inch woofers will fit (anything 26 inch wide or less, will fit).
> 
> So, I am tentatively deciding between a mid-level 12 inch SQ subwoofer such as RE Audio SE/X in a sealed box vs two entry level subs 10inch, such as RE Audio SRX or something similar. I will have roughly 500-600 watt RMS channel to power them.
> 
> Which of these two setups will give better SQ? The pros of dual 10" setup it seems like it will have bigger cone area, so it will need less excursion to play. At the same time, the dual 10" setup does not have a whole lot more surface area compared to a single 12", but it does add more weight and take up more trunk space.


Why not use a 15" instead of dual 12s or 10s?

Dual subs in my experience are just too much. If you're wanting SPL then fine but I'd go 15" like a W15GTI before I'd ever run dual subs. 

I upgraded from a 10" IDQ to a 12" IDMAX to a 12 Shiva MKII and am now using a W15GTI and I couldn't be happier. I still have my IDMAX and the Shiva but I would never go back to them personally. 

A 15 isn't going to be as loud given the same relative specs for 2 12s but it will play lower louder. 

The thing is a 10" isn't more accurate then a 12" or more musical. That is all misinformation. Surface area and Xmax are 2 of the biggest things that influence a subs perceived volume. 1 12" will be able to play the lower frequencies louder then a 10. It is all physics. 

Personally my belief is get the biggest sub you can power and fit. I run my W15GTI off 250 RMS and I am happy.


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## subwoofery (Nov 9, 2008)

sqshoestring said:


> That is what I thought I wrote, maybe it was not clear. I take the largest box acceptable to install then try to put sub(s) in it that work like I want.
> 
> You could make a ported single 12 with more xmax and get pretty low, or run pair of 10 sealed in same volume of space....they would sound different, but some people would like one some the other...that is where a curve helps you. I like the lower one the ported 12, maybe with lots of cabin gain the 10s would be better.
> 
> ...


Sorry for my post. My english is not that good :blush: 
What I said was exactly the same thing as your post... Sorry for the misunderstanding 

Kelvin


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## subwoofery (Nov 9, 2008)

D1g1tal V3n0m said:


> Why not use a 15" instead of dual 12s or 10s?
> 
> Dual subs in my experience are just too much. If you're wanting SPL then fine but I'd go 15" like a W15GTI before I'd ever run dual subs.
> 
> ...


SPL wise, the 15" will be louder off less power when compared to a dual 10' setup - we all know that. 
From your example, the 15" will take up less space than a dual 12s - _usually_ true. 
For some, it might be difficult to fit a 15" height wise. 

Personally, off 600rms, I'd take 1 single sub in a box suited for it - meaning, a 12" 

Kelvin


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## FartinInTheTub (May 25, 2010)

XtremeRevolution said:


> Take the Dayton HO subs for examaple.
> 
> 10": 350 square cm
> 12": 513 square cm
> ...


Agreed


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## ZAKOH (Nov 26, 2010)

subwoofery said:


> SPL wise, the 15" will be louder off less power when compared to a dual 10' setup - we all know that.
> From your example, the 15" will take up less space than a dual 12s - _usually_ true.
> For some, it might be difficult to fit a 15" height wise.
> 
> ...


15 inch subwoofer is a good alternative, but one of my constraints is that the enclosure height can't be more than 14 inches. There are plenty of prefab 12 and 10 inch subwoofer enclosures that meet this height, but 15 inch sub will not work unless I build the enclosure myself to make it face upward... maybe I'll reconsider building the enclosure after all. Right now, my view was towards using prebuilt enclosures like Atrend or Sonic Sub Box because they're cheap and well built.


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## D1g1tal V3n0m (Dec 24, 2008)

subwoofery said:


> SPL wise, the 15" will be louder off less power when compared to a dual 10' setup - we all know that.
> From your example, the 15" will take up less space than a dual 12s - _usually_ true.
> For some, it might be difficult to fit a 15" height wise.
> 
> ...


Compared to 2 10"s yes SPL would be greater from the 15" given both subs specs are in line. We are also talking about dual 12"s being a possibility as well which would be louder then a single 15" from SPL perspective.

The 15" if used could save a dramatic amount of space. I will use a W15GTI as a example. You could make a box H=16.5 W=16.5 D=14 and with sub displacement would net you the recommended 1.5 Net for a sealed enclosure. 
Ported would require some space (4.0 Cu Ft Net).

I noticed the OP said he was limited to 26 width or less which will make it hard to do with 2 12s. 

The money spent on a dual box and 2 10s could be enough to get a 15" and box and save some cash. 

14" height max? This box comes up just 1/2" taller. This would give you a good idea of what you could do to fit a 15 without firing it directly up or down.

Sub Boxes Hatchback Single 15" Subwoofer Unloaded Enclosure Box - 115H

Personally I'd say a 15" and if you really don't want to go that route forget the dual 10s and do something like a IDMAX 12" Ported. I still have my 12" IDMAX D2 I could sell if you decided you wanted that route.


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## ZAKOH (Nov 26, 2010)

D1g1tal V3n0m said:


> Compared to 2 10"s yes SPL would be greater from the 15" given both subs specs are in line. We are also talking about dual 12"s being a possibility as well which would be louder then a single 15" from SPL perspective.
> 
> The 15" if used could save a dramatic amount of space. I will use a W15GTI as a example. You could make a box H=16.5 W=16.5 D=14 and with sub displacement would net you the recommended 1.5 Net for a sealed enclosure.
> Ported would require some space (4.0 Cu Ft Net).
> ...


That box is an interesting find. I think I could possibly make it fit..

By the way, how would 15 inch subwoofer play some higher bass frequencies? I have Alpine Type R components and after some experiments, I decided that 70Hz is the optimal crossover point for them. If I cross at 60 or 50Hz, I end up with relatively weak output in 50/60-70Hz range. My 12 inch subwoofer plays fine up to 70Hz. What about 15 inch subwoofers?


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## ZAKOH (Nov 26, 2010)

D1g1tal V3n0m said:


> Compared to 2 10"s yes SPL would be greater from the 15" given both subs specs are in line. We are also talking about dual 12"s being a possibility as well which would be louder then a single 15" from SPL perspective.
> 
> The 15" if used could save a dramatic amount of space. I will use a W15GTI as a example. You could make a box H=16.5 W=16.5 D=14 and with sub displacement would net you the recommended 1.5 Net for a sealed enclosure.
> Ported would require some space (4.0 Cu Ft Net).
> ...


So, the box that you linked has 2.2cu ft volume. We subtract 0.2cu ft to account for displacement by the driver and then multiply by 1.3 which would be the equivalent box size, once this one is stuffed by appropriate quantity of polyfill. Now, I tried to model a couple of 15 inch subwoofers using WiniSD in this box size. I tried RE Audio SE/X 15 and Dayton Reference HF 15". The thing I noticed about both of them is that there are biggish boomy peaks and low end extension is not as good as it could be. Dayton HF really wants 3.3 cu ft or bigger. RE SE/X wants even more than that. However, the positive side of both is that they need twice less power to achieve the same SPL as my 12 inch subwoofer. I like that aspect of 15 inch subs..

I wonder, do you know of any 15 inch subs that will model better in a 2.6 cu ft enclosure? Or perhaps, do you know if anyone fabricates bigger sealed enclosures?


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## subwoofery (Nov 9, 2008)

ZAKOH said:


> So, the box that you linked has 2.2cu ft volume. We subtract 0.2cu ft to account for displacement by the driver and then multiply by 1.3 which would be the equivalent box size, once this one is stuffed by appropriate quantity of polyfill. Now, I tried to model a couple of 15 inch subwoofers using WiniSD in this box size. I tried RE Audio SE/X 15 and Dayton Reference HF 15". The thing I noticed about both of them is that there are biggish boomy peaks and low end extension is not as good as it could be. Dayton HF really wants 3.3 cu ft or bigger. RE SE/X wants even more than that. However, the positive side of both is that they need twice less power to achieve the same SPL as my 12 inch subwoofer. I like that aspect of 15 inch subs..
> 
> I wonder, do you know of any 15 inch subs that will model better in a 2.6 cu ft enclosure? Or perhaps, do you know if anyone fabricates bigger sealed enclosures?


You play with 15s sealed? If yes, then just look at the F3. Too low and it's gonna sound boomy due to cabin gain. 
I usually find an F3 between 40Hz and 55Hz to work well in a car. 
Using WinISD, you need to care for the Xmax figures too. The 15"HF for example will over excurt way before reaching 20Hz if you go bigger than 2.5cuft and enough power. 

Kelvin


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## ZAKOH (Nov 26, 2010)

subwoofery said:


> You play with 15s sealed? If yes, then just look at the F3. Too low and it's gonna sound boomy due to cabin gain.
> I usually find an F3 between 40Hz and 55Hz to work well in a car.
> Using WinISD, you need to care for the Xmax figures too. The 15"HF for example will over excurt way before reaching 20Hz if you go bigger than 2.5cuft and enough power.
> 
> Kelvin


Maybe it's also a matter of taste. My current sub is Re SRX 12, with modeled F3 of 45 or so. It sounds fine. I like it. But, I personally wouldn't mind a bit lower F3. Perhaps at 40Hz.

By the way, I just tried Dayton HO 15" and it does model quite well in the box linked above. I forgot that HO are the ones that work ok in smaller boxes. HF generally need much bigger boxes. But interestingly, RE SE/X 12" models even better.. lower F3 (40 vs 45Hz) and deeper bass extension.. of course.. it's all mumbo jumbo.. it was be interesting to hear about actual experiences with HO 15". I know SE/X 12" already has good reviews.


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## subwoofery (Nov 9, 2008)

ZAKOH said:


> Maybe it's also a matter of taste. My current sub is Re SRX 12, with modeled F3 of 45 or so. It sounds fine. I like it. But, I personally wouldn't mind a bit lower F3. Perhaps at 40Hz.
> 
> By the way, I just tried Dayton HO 15" and it does model quite well in the box linked above. I forgot that HO are the ones that work ok in smaller boxes. HF generally need much bigger boxes. But interestingly, RE SE/X 12" models even better.. lower F3 (40 vs 45Hz) and deeper bass extension.. of course.. it's all mumbo jumbo.. it was be interesting to hear about actual experiences with HO 15". I know SE/X 12" already has good reviews.


However, as stated in my previous post, I find it useless to have a box that models F3 @ 40Hz if it reaches max excursion @ 35Hz (just an example). 
I usually input the wattage and play with the box size so that excursion maxes @ 20Hz and not above. 
Having too much low end is a good thing (at least to me), I like to EQ the low end to my taste by cutting instead of boosting... 

Kelvin


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## D1g1tal V3n0m (Dec 24, 2008)

ZAKOH said:


> So, the box that you linked has 2.2cu ft volume. We subtract 0.2cu ft to account for displacement by the driver and then multiply by 1.3 which would be the equivalent box size, once this one is stuffed by appropriate quantity of polyfill. Now, I tried to model a couple of 15 inch subwoofers using WiniSD in this box size. I tried RE Audio SE/X 15 and Dayton Reference HF 15". The thing I noticed about both of them is that there are biggish boomy peaks and low end extension is not as good as it could be. Dayton HF really wants 3.3 cu ft or bigger. RE SE/X wants even more than that. However, the positive side of both is that they need twice less power to achieve the same SPL as my 12 inch subwoofer. I like that aspect of 15 inch subs..
> 
> I wonder, do you know of any 15 inch subs that will model better in a 2.6 cu ft enclosure? Or perhaps, do you know if anyone fabricates bigger sealed enclosures?



If I were to go 15" I'd recommend a W15GTI. It will do IB, Ported, or sealed. I did some modeling in WinISD and you'd be around maybe -6db with the box stuffed with polyfill (2.5 Cu Ft Net. Speaker displacement is .13. Maybe 3db down at 30Hz or so. 

In all honesty we're not talking about Home Theater here so I tend to look for something that can stay within -3db at around 28-30Hz for in car. You can do a little boosting on the low end if you wish but I prefer to not.

W15GTI parameters are below with a couple designs for boxes for the

http://www.jbl.com/resources/Brands...nts/en-US/BoxesandParameters/W15GTi_rev_f.pdf


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## sqshoestring (Jun 19, 2007)

Inverted can help, I have a 10 in a 1cf premade box ported. Inverted it has enough volume to get lower it made a difference, the stuffing helped too. This particular sub is blinged up, I don't care but it looks pretty cool inverted. Its just a test sub I use that I scored cheap on epay one day, an alphasonic 400rms. Still have to try in a car it gets under 30 but SPL might be low who knows. In the house it makes things rattle.


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## ZAKOH (Nov 26, 2010)

D1g1tal V3n0m said:


> If I were to go 15" I'd recommend a W15GTI.


It looks good, but definitely it's one of the more expensive subwoofers out there. It'll depend on my budget if I am going to buy one..


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