Is more displacement always better, even with the same power?

[I Like Waffle]

Im coming up with ideas for my next setup and i was wondering this, lets say for example, i have 2 15" type Rs in a ported box to spec, on 1500wrms, or lets say i have 4 type r 12"s in a ported box to spec, both same type of box, same vehicle, same amp, etc. Which would be louder and why?

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[power-fanatic07 5,000+ posts]

4 12's would be louder you would have more cone area.

but at the same time you're giving each 12 less power and im guessing 750 is their rms?

i don't know...i still say the 4 12's would be louder...

 

[Xprime4 10+ year member]

That rule ain't 100% right imo. I had two 15inch and downgraded to two 12inch and i'm a lil louder. Box for the 15 wasn't big enough (like 3.3 per sub)

go with more 12s

 

[Plutoman 10+ year member]

For the same amount of power and same subs, displacement makes a difference and is always louder. You have more cone area with four twelves than with two fifteen's.

 

[Plutoman 10+ year member]

That rule ain't 100% right imo. I had two 15inch and downgraded to two 12inch and i'm a lil louder. Box for the 15 wasn't big enough (like 3.3 per sub)
go with more 12s

Assuming you have a correct box, and a correct installation, it is 100% right. Should've just built a new box and you would've been fine.

 

[mokedaddy 5,000+ posts]

Assuming you have a correct box, and a correct installation, it is 100% right. Should've just built a new box and you would've been fine.

Its actually car dependent. What works in a SUV is not necessarily going to work in a trunk car.

Two 10s get louder in my car than two or even three 12s, one fifteen, one eighteen or four 10s. All in correct enclosures.

 

[Plutoman 10+ year member]

For the different sizes of subs, you might try a different placement. It's pretty simple physics over the displacement. Putting the subs in a different position in a vehicle, facing a different direction, etc, will allow a different resonance through the vehicle. It's all in the installation.

 

[mokedaddy 5,000+ posts]

No. If that was the case why wouldnt competitiors just throw as many subs as they can fit into their cars?

Yes displacement is a factor but far from the only factor.

 

[Plutoman 10+ year member]

Well... If you read, I said assuming the same power, the same type of subwoofers, and a completely correct installation, displacement is really the only remaining factor left.

There's a hell of a lot more that goes into an SPL comp. And a lot of it is getting that correct installation to use the subs to their utmost potential.

 

[mokedaddy 5,000+ posts]

Well... If you read, I said assuming the same power, the same type of subwoofers, and a completely correct installation, displacement is really the only remaining factor left.
There's a hell of a lot more that goes into an SPL comp. And a lot of it is getting that correct installation to use the subs to their utmost potential.

So why are two 10s louder in my car vs the same exact 12s? With many hours of testing?

Its never cut and dry and there is no hard and fast rules so unless you have tried something you should never assume. It can possibly be used as a guide but to say displacement is the only factor is uneducated.

If the wave does not have enough room to develop it wont be as loud. There is an outside factor you didnt take into account. Trust me there are many more.

 

[mokedaddy 5,000+ posts]

Also there is more to displacement than cone size.

One example Boston pro 10.4s actually had more displacement than the pro 12.4 of the same line. Why? More excursion. They were simply louder.

 

[Plutoman 10+ year member]

Hmm. Telling me about assuming... Well, if you read what I said. Displacement is not the only factor. But with everything else equal, it is.

Now, I'm going to take a guess here that you've never done hours of testing besides setting gains. Trying multitudes of box positions, locations, etc. Running sine sweeps on every one of them. I would love to see videos and pictures of you running tests on these twelves and then moving to the tens.

Notice what you've said. If the wave does not have enough room to develop, it won't be as loud. What moving the box around does will change that. It opens up the resonant frequencies. You can call me uneducated if you'd like, but simple physics will show that displacement will rule out.

 

[Plutoman 10+ year member]

Also there is more to displacement than cone size.
One example Boston pro 10.4s actually had more displacement than the pro 12.4 of the same line. Why? More excursion. They were simply louder.

By saying the same sub, I assumed you would realize I meant with similar specifications. I.E. - a ten inch sub reconed to a twelve will be louder, not by much, but it will be - assuming the new installation is correct for the twelve. Including a box size to spec.

 

[I Like Waffle]

Subs will be facing up port back if that makes a difference. Last setup was subs back port back, current setup is subs back port back. Subs up port back sounds about the same and is easier to do so imma do that

 

[Plutoman 10+ year member]

Going from two 15's to 4 12's, both ported, the four twelves will almost certainly be louder. My recommendation.