Printer Friendly Forum Posts - Whats better, 2 12’s or a 15

if you take 1 15" sub and 2 12" subs and put the same amount of power to them the 15 " sub will be louder due to the fact that your 15" sub will be moving twice as far because you will not be sliting the power between the subs like you would be with the 12"s check out www.ikesound.com you can get you can get a good 15" sub for under $200

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1974 ford pinto 4 15" punch Z power punch bd 1001 pioneer DEH-6700

ok i thought if you ran more cone area you would have more sound pressure i was allways told every sub you add to a point would increase by 3bd given proper power so i would say 2 12s would be the way to go and you could try to go to https://sonicelectrnix.com/index.php and you may find some good deals on subs

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live loud

Really they would be very similar volume wise, in my opinion the 12s would be slightly louder (or at the very least will create a little more vibration) due to the larger cone area. However, most people I know have a hard time going back to 12s after having 15s, they are a little slower and sloppier in general but the depth and the lows you get out of a fifteen are purely addicting.

First, I have to address where you are purchaseing your product due to the links listed above, Buy the piece you find to be most effective to you price wise and proformance wise, then purchase you part from a LOCAL dealer. These internet sites give you great pricing but the product may be and usually is Remanned or repaired, used or just trash. All the BIG company's have very strick regulations against the sale of their products by persons unauthorized, or unless an AUTHORIZED internet dealer, the parts will not come with a wanentee, either expressed or implied. Know your salesman! Kepping the local shops up and running is where all the expertise comes from on this site. And when your in need of help those internet guy are going to disappear. or never answer the emails, Just a warning

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*ALwaYs KnoW YoUr SaLEsmAN!!*

someone wrote:

However, most people I know have a hard time going back to 12s after having 15s, they are a little slower and sloppier in general but the depth and the lows you get out of a fifteen are purely addicting.

That's unture. A 15 can be just as fast as an 8. It all depends on the motor driving it.

I've seen eights that were very slow(muddy), and I've seen 15s that would crack like a whip(fast)

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i have some questions are you going for SQ or SPL ? what amp are you going to run? and what vehicle is this setup going in ? these are some things that will effect what would be the best choice

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1974 ford pinto 4 15" punch Z power punch bd 1001 pioneer DEH-6700

God, you guys are killing me. Making general statements like " a 15" would be twice as loud because your not splitting the power in half " and " every time you add a sub you get 3 db" have no factual foundation what so ever. Box size and type, drive motor ( voice coil and magnet ), impedance and cone/surround have SO much more to do with quality and level of sound the cone diameter. Poorman started to scratch the surface with his answer. Go to your local indpendent dealer and listen to ported vs. sealed enclosures. Listen to single vs. multiple drivers. Listen to a single more expensive sub vs. multiple cheaper ones. This will start to answer your questions.

A couple of notes, the most efficiant box on my showroom is a triple 12" W1V2 JL sealed box ( so much for splitting up power )

The best SQL box on my floor is a single JL 12" W6V2 sealed box ( so much for theorys )

[QUOTEA couple of notes, the most efficiant box on my showroom is a triple 12" W1V2 JL sealed box ( so much for splitting up power )[/QUOTE] what i was trying to say. was that if you were to take 2 12" svc and a equal 15 dvc sub and run the same amp at 2ohms with the 12"s and the 15" sub in the correct enclosures the 15" sub would produce more SPL if this is incorrect i am always more than happy to learn somthing new

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1974 ford pinto 4 15" punch Z power punch bd 1001 pioneer DEH-6700

Point is, thru this whole thread nobody mentioned box type or size, impedance, woofer type or power availability. There were just a bunch of general statements with no details or facts to back them up. How can these statements be taken seriously with no context?

How can you recommend JL W1v2's is the real question.

Listen, if you like a woofer that drops mad mad mad low, go with a 15. If you are looking for more impact and have a good size amp, hook up a pair of 12''s DVC4 ohm run them parallel and you get some serious current running. You'll be running 24" of cone v. 15" of cone, but you won't get lower than the 15". The 12"s will provide more impact because their are two of them (providing they are the same make) than the 15"

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"I don't play games. I play Nakamichi and that for real yo" - Probably some japanese kid said this in the early 80's trying to sell stereo out of his trunk lol.

What do you mean by "impact" ?

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Point again is, NO ONE mentioned price, box size, power, box type,room available in car or power. If you don't know any of these things how can you say which is better? I didn't recommend 12" W1V2 I only said that with equal power they were the most efficiant woofer on my floor to question the "splitting of power" theory. A lot of subs use differant motor assemblys for the same make and model of sub depending on size. If your 15" sub had a larger drive motor ( magnet and voice coil ) then your twelve would you still make your blanket statement about performance due to cone area? I think not. Buy the way, if somebody said they had around $220 to spend on a pair of 12" woofers, I would recommend the JL W1V2s.

now I didnt mention box type or power because those werent the factors in question, not to mention box type leads to a completely different discussion as far as sacrificing quality for volume. He simply asked a very broad question which was what is louder 12s or a 15, I assumed this was comparing the same subs, because anybody can look at a single 15" fosgate p1, and compare it to two kicker l7 12s and realize the kickers (all subs are in a sealed box for comparison reasons) will probably blow the p1s out of the water. Now as far as what I said about the 15s being slower that was a generalization, and once again comparing two of the same subs just different sizes, Ive heard the older jl 15w6s and been very surprised at their speed and clarity, and at the same time been blown away by an 8w7's depth. The point is, there are always certain exceptions, it was a broad general question, he gave very few specifics, so we didnt narrow down the answer too much on him.

tcss, i don't know what your problem is or who you think you are, but my point needed none of the above information that you said it did.

Period, two 12"'s provide more impact than a 15 (granted they are the same model and enclosure). Thats a given (duh). Driving power, well, just make sure even incriments get to them. Take a 1000 W amp and put 250 WRMS into each woofer (lets say 2 ohms tcss :) ) and run a total of 500 WRMS. Well, lets take that 15" and put the same amount of power (remember, this is the same model speaker in the 15") Efficiency is not really an issue with 500 WRMS compared to the 12, as it probably is about 2db and you'd need to double your power to get more out of it. The 24" of cone will provide more sound per unit of power as well as impact, just because of sheer surface area.

Switch the enclosures, that's different. 1 15" in a ported could blow down the house over 2 12" sealed.

JL W1V2 is a horrible woofer. I'd recommend it to no one except the idiots that work for that company. Get some Nakamichi SPW120's. They are worth it and sound good for like $70 a piece.

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"I don't play games. I play Nakamichi and that for real yo" - Probably some japanese kid said this in the early 80's trying to sell stereo out of his trunk lol.

Ooooooh a little testy today are we? Here's a couple of thoughts. What is impact? I've never heard that as any sort of sound measurement.Efficiency is always an issue. To get the 2 db differance ( your guess ) between the 15 and the twelves you would need between 800 and 900 watts RMS. Pretty big price jump in my eyes for someone on a budget.

Did the JL truck run over your wagon when you were a child? That' some pretty pent up anger you got going on there.My customers LOVE their JL 12" W1V2s.

Twenty three years in business. Over 60,000 cars done. You?

Oh come on tcss, u think u know audio?

Ahahaha. *sigh*

I kill myself.

Anywho, ya know what I always look at? Cone AREA.
1x15" = 175 sq in
2x12" = 226 sq in

I think this is pretty much the easiest way to answer "what is gonna be louder" at a given power, holding box size and impedence and whatever tcss needs to make a call at a constant.

Yea JL woofers always leave me a little cold. I have NOT, however, heard the w1. I can say authoritatively however, that the w0 was absolutely pathetic.

I, out of hand, completely DISMISS anyones opinion on audio equipment when they PAID to have it installed.

For that matter, I know a guy that LOVES his bazooka tube.

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"I'm finished!" - Daniel Plainview

Sedate, always love your sense of humor. Ya know, rough day, couldn't get the Alpine IVA-D310 to see the XM tuner in the $500K motor home. Un caring customer, need to get it done by the end of the day deal. Go find a dealer who has a JL 10" W1V2 in JLs own slot loaded box. Let me know what you think ( PM ). Where is Steven Kephart when you need him?

Huh? I mean, I didn't think anything you said was wrong, I was just being a little incubus. And I, like uthink, like to throw crap at JL woofers. I can't begin to tell you how much distaste I have for my $500 w6 eh?

Naww, I actually think the w1 looks pretty good. Much more substantial than the little hockey puck magnet on the w0. I like the new cone to. Decent excursion for the RMS and push-pin connections.

If I get a chance to take a listen, I'll let ya know.

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"I'm finished!" - Daniel Plainview

I don't think you'll get a 2dB increase using two 12s over 1 15in sub.

The cone area difference is ~30% more for the 2 12s. Now using the basic rule of thumb that a doubling of cone area equals a 3dB increase we find out that you would get ~0.9dB increase with the 2 12s.

Now this is assuming that ALL variables remain the same. If anything else changes then you can't make any arguement for or against either.

I have a question: Why do people have a misconception that a larger sub will be able to play lower frequencies at higher amplitudes? EVERYTHING depends on the SD of the driver. It's possible to have a 12 that has a higher SD then a 15 if the 12 has a long excursion, and the 15 has a short excursion.

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Yay! Sedate wins the booby prize for accurately explaining cone AREA versus cone DIAMETER. (sorry to those who thought 2x12" = 24" of cone area)

Second place goes to Poormanq45 for epounding on the virtues of size versus frequency.

And the top award for best flame goes to tcss for, "Did the JL truck run over your wagon when you were a child?" ROFL gotta love the wit!

Good job, guys. Thanks for making the day a little brighter posted_image

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VEHICLE: 2002 GMC Sonoma ZR2
Alpine CDA-7940
AudioControl EQT x2
JL Audio 1000/1
JL Audio 10W6 (originals) x3
Kicker ZR120
Kicker ZR460
Polk GXR-6 x4
Polk GXR-4 x2

Thank you guys for finally showing up. Sedate, Poorman and Paradigm, you made my day.

The booby prize!! Woot!

Poormanq45 wrote:

Why do people have a misconception that a larger sub will be able to play lower frequencies at higher amplitudes? EVERYTHING depends on the SD of the driver. It's possible to have a 12 that has a higher SD then a 15 if the 12 has a long excursion, and the 15 has a short excursion.

Uhh.. dude. The radiating area of the driver (sd) is inherently tied to the diameter of the driver.... i mean.. common sense tells us that.

The excursion thing? A 12" with a long excursion will have a larger surround, thus, LESS radiating area, while a 15 with a small excursion will have a smaller surround, thus MORE radiating area.

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"I'm finished!" - Daniel Plainview

lol, people trying to tell me about SD.

My when I was your age, Denon just came out!

Now,i've had 30 years of install/audio experience, and more cars than i can count. I am a professional electrical engineer as well. I dominate with audiophile and SQ knowledge that could make your brain fold in. U think U know audio, you are wrong tcss. last time i checked 30 > ur X years (if they are valid)...

JL's truck sucks... They are garbage (W1v2) as well as 1/2 off there other products. I'll never buy a JL product as they are overpriced. Don't say what bug jumped in my ass about them, many years of working with their equipment makes me disfavor it over other better brands for less money.

All you need to do is 2x power to take advantage of efficiency is you do it right. By the way, if you don't know what impact is, you are an idiot.
Impact is the physical measurement of how much sound you feel from low frequencies (aka how hard your subs hit). No tool, just pure physical measurement. My 3 15"s will hit harder than 1 10 obviously. You can tell when you get in the cars!

IMPACT IS NOT EXTREMELY IMPORTANT FOR ALL PEOPLE...just bassheads or SQ people that tend to like bass.... :)

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"I don't play games. I play Nakamichi and that for real yo" - Probably some japanese kid said this in the early 80's trying to sell stereo out of his trunk lol.

You really got to start talking in complete sentences it makes you sound much more intelligent. That's just how long I've owned my store(s). Do you know what a Craig power play is? Who made the first coaxial car speaker?Who made the first car stereo amp? Who is Rich Coe? What was the best woofer Car Audio Magazine ever tested? I'll give you this one ( 12" JL W6V2 ) Best car they ever heard? ( JLs Mini ). You really should consider anger management. I started doing this when I was 18 in a real live stereo shop. 1973 but who' counting.

What is "impact " measured in? Wrench units?

Twice the power only gives you 3 db.

Happy Trails

uthinkuknoaudio wrote:

I dominate with audiophile and SQ knowledge that could make your brain fold in.

Just luv that line. Don't mind if I quote you in my sig line, do you?

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

as a nice comparison on cheap setups i offer up my 2 systems, system one is a sony head unit, an alpine m350 amp running at 2 ohms and a cerwin vega 15 hed sub in a sealed enclosure...the second system is an ma audio amp running 180watts per channel to 2 kicker comp 12" subs in a ported box being run by a pioneer head unit, both systems are loud but i've had both boxes in my car being powered by the same amp with 12ga power wire.

the 15 hits hard enough to vibrate windows and cars around me modeled it shows 119 db i have yet to have the car metered but i know its extremely loud, with the same amp setup for the 2 12s i lose alittle bit of volume, keep in mind both setups run at 2 ohm given my choice i prefer the 15, and as for 15s being slow, i can play 50 cent or 36 mafia and pound nice and low all day then throw in some mudvayne or better yet dream theater and the sub keeps up just fine with the technical bass drum parts, never sounds sloppy or behind the beat at all, grand total for the setups......the 15" and alpine i've got about 350 in with the box, with the ma audio amp and 2 kickers and a store bought box i've got a little under 400, both systems are very loud and fill the need very nicely, and buy local it saves headaches later, i orginally had a memphis audio pr15 dvc sub but it blew up and no local dealers so i had to get it online, i went local afterwards spent twice as much and blew up my next cv sub but the dealer looked at it and replaced it no hassles...anyone local to osage beach check out epic audio awsome customer service, there is also a store in kansas somewhere :).

I love seeing brain vs brain here on the forums. In the end it's opinion vs opinion or experience vs what is written in a magazine. Just had to throw in my 2c's on this pride crushing issue

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Jeff
Velocity Custom Home Theater
Mobile Audio/Video Specialist
Morden, Manitoba CANADA

sedate wrote:

Uhh.. dude. The radiating area of the driver (sd) is inherently tied to the diameter of the driver.... i mean.. common sense tells us that.

The excursion thing? A 12" with a long excursion will have a larger surround, thus, LESS radiating area, while a 15 with a small excursion will have a smaller surround, thus MORE radiating area.

Oops, I meant to say SD x Xmax. It is quite possible to have a 12in sub with a larger displacement(sd*xmax then a 15in driver.

I do agree that a larger excursion will reduce cone area by increasing the size of the surround.

Ok then, lets use the numbers that someone provided earlier.

1x15" = 175 sq in
1x12" = 113 sq in,
convert that to mm and you get
1x381mm = 113951.385sq mm
1x304.8mm = 72928.8864sq mm

So then, at 1mm excursion the 15" displaces more air. Now, if the 12in moves 2mm and the 15in moves 1 mm, then the 12 displaces 145857.7728sq mm, and the 15 displaces 113951.385sq mm

So as you can see. It is quite possible for a 12 to displace more air volume then a 15.

It all depends on SD and Xmax

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uthinkuknoaudio wrote:

lol, people trying to tell me about SD.

My when I was your age, Denon just came out!

Now,i've had 30 years of install/audio experience, and more cars than i can count. I am a professional electrical engineer as well. I dominate with audiophile and SQ knowledge that could make your brain fold in. U think U know audio, you are wrong tcss. last time i checked 30 > ur X years (if they are valid)...

JL's truck sucks... They are garbage (W1v2) as well as 1/2 off there other products. I'll never buy a JL product as they are overpriced. Don't say what bug jumped in my ass about them, many years of working with their equipment makes me disfavor it over other better brands for less money.

All you need to do is 2x power to take advantage of efficiency is you do it right. By the way, if you don't know what impact is, you are an idiot.
Impact is the physical measurement of how much sound you feel from low frequencies (aka how hard your subs hit). No tool, just pure physical measurement. My 3 15"s will hit harder than 1 10 obviously. You can tell when you get in the cars!

IMPACT IS NOT EXTREMELY IMPORTANT FOR ALL PEOPLE...just bassheads or SQ people that tend to like bass.... :)

Started when you were 16, huh? Do many 8-track installs? Or were those too "overpriced" for you? posted_image

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VEHICLE: 2002 GMC Sonoma ZR2
Alpine CDA-7940
AudioControl EQT x2
JL Audio 1000/1
JL Audio 10W6 (originals) x3
Kicker ZR120
Kicker ZR460
Polk GXR-6 x4
Polk GXR-4 x2