# 2 10" or 1 15" Sub?



## Eclipto (May 1, 2014)

I am trying to get some more bass out of my system. Right now I am running two Soundstream T7.102 sub woofers in a sealed enclosure off a Soundstream TN1.1200D mono-block amplifier. I want to either build a custom fit ported enclosure for these two 10s, or buy a 15inch subwoofer and build a custom fit ported enclosure for it.
What would be a better idea? I'm on a tight budget and don't want to buy a new amp. The box will be professionally built, and I don't want to spend more than $300 on a 15inch sub woofer. Would keeping my two 10inch subs in a ported box be just as loud as 1 15inch sub in a ported box?
All advice would be really appreciated. Depending on answers I may need help finding a nice 15inch sub for just under $300


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## syc0path (Jan 23, 2013)

2 10s have the same cone area as a single 15. So all other things being equal, u will get about the same output. Of course, u could build some crazy SPL setup for the 15 and then it will be way louder than the 10s, but then there would be other trade-offs.

Since u already have the 10s, keep them. Switching to a single 15 isn't going to give u the improvement in SPL that u want. It just wouldn't be worth it for the $$.


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## boarder124 (Mar 16, 2006)

port those 10's in 1.5 cuft each at around 25-30hz and then youll be glad you didnt spend money on a 15.


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## hot9dog (Mar 23, 2013)

Im on the fence with this one. I love the sound of properly ported 10's. Its a good balance i feel for a system that plays all kinds of music, but........ in my daily driver i have a sealed mb quart pwe 352 15" (Rockford built) and am in love with the low end extension! But there is a trade off for that setup also. I say port the 10's and live with it for awhile...... and then keep your eye open for a 15. You can never have subs... lol. Then you can swap them out back and forth.


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## theoldguy (Nov 17, 2009)

"professionally built" lol I love that term. Cracks me up every time. anywho....I would agree with the comments so far suggesting to keep the 10"s that you have and change the enclosure. No sense in starting from scratch when you already have the tools to achieve your goal.


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## Eclipto (May 1, 2014)

"proffesionally built" meaning someone who works on such projects as a profession... I have a phillips and maybe utility knife in my house... hahaha 
Anyway I hear that a great tune for all around bass is at 36hz? But a tune around 31hz hits really low?


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## qwertydude (Dec 22, 2008)

I would try porting those Soundstreams. It's sorta tough to get a decent response out of them with a .51 Qts. But there's a few ways you can go. For the flattest response you'd really want 2.2 cubic feet at 25 hz (red line in the pic). Unfortunately high Qts subwoofers tend to need very low tuning to be able to hit really low notes and play flat.

Going with their recommended box of 1.5 cubic feet at 35 hz (black line) lends a pretty peaky with a +4db peak at 40 hz very good efficiency. But this though tends to make the subwoofer sound like a one note boom machine.

4 CU ft Custom Vented Dual 10" MDF Car Subwoofer Box Enclosure Tuned 32Hz | eBay

Since you're not building your own box and likely will go premade. I can definitely recommend my favorite ported box, it's about the least expensive box that will give decent sound quality with those woofers, definitely getting one made would likely cost you significantly more than $150. The Mobile Soundworks is 2 cubic feet tuned to 32 hz (green line), in real life I've measured these boxes tend to be tuned to 30 hz. This gives a +3 db peak at 33 hz which is a better frequency to have your peak at since it's gives you response to the lowest registers of bass in music and maintains more efficiency than the subsonic 25 hz tune that gives a completely flat response.










I've simulated these boxes for you. You can see the 2 cubic foot box tuned to 30 is the best compromise between the two. Playing flat to 25 hz with a large low tuned box really won't benefit you all the much since most music never goes below 30 hz.

Compare the ported boxes to the sealed (blue line). At 33 hz you've got 10 db better response than sealed. At 100 watts ported to get that kind of output sealed, you'd have to run close to 1000 watts sealed! So if you were thinking going one 15 sealed which would be about the same as two 10's sealed vs two 10's ported. 2 10's ported any day.

This is probably the most budget friendly way to upgrade your sound. Use your existing woofers, existing amplifier and only have to buy a box vs buying a subwoofer and a box.


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## bassfromspace (Jun 28, 2016)

Big subs pack a visceral impact that you just don't find in smaller subs. Think of it in terms of horsepower vs torque.


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## qwertydude (Dec 22, 2008)

It's about cone area. Sure more cone area is better and will provide more bass but really with two 10's you have almost the same cone area as the 15 but you have twice the motor strength.

So motor strength being the big driving force vs surface area you'll get better efficiency in a smaller ported box than with a weaker motored but larger subwoofer trying to go ported in an even larger box.

Thinking of it horsepower vs torque. If you have the transmission that can put the horsepower to the ground effectively, in this case the box is the transmission, hp to hp it wouldn't matter what the torque is. Performance would be pretty much identical. But the advantage would definitely go to the lighter weight car with two motors.

So really it can be a wash, the 15 can better or the two 10's. But all else being equal between the subwoofers the two 10's with twice the motor force will be the more efficient setup that can extract more performance out of a ported box.


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## quality_sound (Dec 25, 2005)

Every single time I've compared a pair of tens to a single fifteen, I have MUCH preferred the fifteen. 

Sent from my Moto X using Tapatalk


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## papasin (Jan 24, 2011)

Just FYI...

Two of these ---> One of these
8"*--->*11"
10"*--->*13.5"
11"*--->*15"
12"*--->*18"
15"*--->*22"

source from (along with other useful info):

http://www.caraudio.com/forums/general-discussion/497240-cone-area-relation-chart.html


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## qwertydude (Dec 22, 2008)

quality_sound said:


> Every single time I've compared a pair of tens to a single fifteen, I have MUCH preferred the fifteen.
> 
> Sent from my Moto X using Tapatalk


Are we talking subwoofers in the same class like say two Sundown SA-10's vs one SA-15? Because in that scenario an SA-15 would only be able to run sealed with a Qts of .65 vs the .48 of the SA-10. Trying to port a sub with .65 Qts would lead to humongous boxes bigger than the two 10's would require.

So in this case having two motors is definitely a benefit as the greater motor force lets you run ported which will both play more efficiently than the 15, and the undermotored 15 ends up either running sealed or needing a much larger box than the two 10's.

If it was down to a 10 vs a 15 more than likely the 15 wins out. But running multiples is a valid way to get sound quality and output and maintain smaller box requirement totals.


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## Eclipto (May 1, 2014)

the biggest issue about this project is the limited space. I know 88% of people think it's lame in terms of sound staging, but I have 4 8" coaxials in my trunk along with the two 10" subwoofers. (my reason being I am often opening my hatch to supply music for parties, chillaxing, so on... right now I have the coaxials in a small custom box ontop of a custom sub box.) 
in summary, I need to have the dimensions of my trunk measured out and custom box built anyways. I accept the additional cost to keep what I enjoy most in my trunk!! 
On another note, qwertydude... I need EACH subwoofer separated into 2 2.2 cubic feet chambers ideally... correct? Right now, in my sealed box I am running both subs in the same box without a separation wall.


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## qwertydude (Dec 22, 2008)

Ideally yes you'd want each sub in a separate enclosure to keep them safe. If you have a shared enclosure of 4.4 cubic feet and a single port that won't be a problem. But on the off chance one subwoofer blows at high volume a common chamber box will unload the still working subwoofer and that subwoofer would go into pretty serious overexcursion and could bottom out and break.

The separation will prevent this. But it's not entirely necessary to work, it'll work fine sharing space and you'll save some box volume in the process but separating the woofers is added precaution just in case something goes wrong.


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