mixing sub sizes?

Prepare to spend money and time.  You should use an active crossover to separate freqs.  And be mindful of the fact that with the sub in the trunk crossed at 60 or 50 Hz, you won't get much out of it.  All the same rules of building proper enclosures would be in effect with the rear-shelf-mounted subs, too.  And the shelf itself will have to be fortified mightily with damping because it will make noise if you don't.

All in all, multiple driver setups are difficult to get good results from.  But if you are willing to put the money and testing and time into it, you can achieve a greater system.  Do you already have the front main speakers separated into 3-ways?  Prob. not....if you did you wouldn't have posted this question, because you will have already experienced what you have to go through to get it right.

The sticky subject Advanced front how-to will give you a lot of info to start with.  Meanwhile, you're much better off replacing the front speakers with a pair of components, since you are obviously not happy with the current tweeter setup.  This will keep your system with just one pair of tweeters in the front soundstage.  Go listen to some different brands.

Per your other question, yes...the 12 and the 8's will be sharing sub duties so you would have to separate sub frequencies accordingly.  You will double or triple your cost of this system, and without benefit of the tuning tools needed (see the linked thread) you are likely to end up with sound that is not any better than keeping it simple.  Consider, instead, a rebuild of the "same old" with new information you can find in this forum.

As S. Kephart said in that thread, "But my question is why?"

Too often this question on mixing sizes comes up not because of strategy, but because those drivers happen to already be on hand.  A careful read of the author's words will indicate where one should go with an answer. 

I'm willing to bet that in most cases there is a dissatisfaction with what gear is currently in place...and that most people don't want to do a complete uninstall of equipment that has at least SOME merit...thus the question of adding to instead of replacing.

People end up with two or three sets of tweeters and mis-matched woofers in their cars....and wonder why they can't get the sound right, so  there should aways be a word of caution.  Stick to the basics unless you've mastered those and have the knowledge and experience to venture into new territories. 

If this thread is based on a strategic endeavor to use two sizes of subs I'll eat my hat.

Myself?  Still trying to master the basics.  And BTW, I have an edible hat tucked away for emergencies...;)

audiobhan101 wrote:

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Should you seperate frequencies when you have 3 or more of the same size subs? or does this only apply when mixing sizes?
I have never had any probs with by MA audio's or Audiobahn's cancelling each other but will i get better results seperating the frequency?

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No, multiple subs of the same size should play the same frequencies. Only multiple sized setups will need the varied x-over points.

Going to throw this in because I didn't see anyone mention it.

If properly tuned AND installed the multiple size subs WILL give you better SQ then having a single(or multiple of the same size) play the whole bass range.

You mentioned that you have the 8s in the rear shelf, and the 12 in the trunk.  This is not the best setup for SQ.  The subs are interacting with each other, usually for the worse.

I'm interested in doing the same thing in a 95 Honda Accord LX.  It seems like all that you would have to do is add a crossover to the system and cutoff the 8s slightly before the 12 peaks.  Is this true or am I way off base here.  I apologize for the noob question, but I would really like to know.  I had BOOMY systems when I was younger, but now I listen to more Jazz and Rock.  If the sound is truely that much better I'm willing to invest in it.  I drive quite a bit.  Any help on how to achieve this would be much apreciated.

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