Iv'e heard differnet people ask, " what is better, 2 15" subs or 2 12" subs, why can't they just put a 15" sub and a couple 12" subs. So why isn't there combonations of diferent sizes, that would seem to be the ideal system?
same reason you don't see school buses on drag strips. different horses for different courses.
smaller subs are faster and more responsive for detailed music, where larger subs have the overwhelming, deep resonance bass-heads are after. You can't combine them in the same system and get an ideal mix of both. if you want tight, sharp bass, and you throw a 15" sub in with some 8" subs, the fifteen will invariably overpower the smaller subs, and the sloppiness of the fifteen will negate any tightness teh eights have. By the same token though, if you're after a lot of deep, hard hitting bass, the smaller subs will feel weak and pointless, and sticking to larger subs with more mass and a lower Fs will yield the results you seek. It's a matter of choosing the components that meet your needs. remember, the best systems are invariably the simple ones. Simple, clean, sleek, and well designed, installed, and tuned.
example, instead of using a crapload of speakers, amps, etc.. my next system will consist of: a head unit (source) 2 1/3 octave EQs (competition tuning) 1 pre-amp (in-dash for volume, fade, balance, EQ, and signal balancing) 2 amplifers (front stage, and subs) 1 3-way component set in front 2 12" subs in sealed or AP glassed enclosures.
that's it. pretty straight forward. going purely for SQ, and not SPL obviously.
hehe i was thinking about getting a 15" brahma extreme or 15" titanium pro and a pair of like 10w7's and run one amp to the w7's and one to the 15, run a few switches up the the dash and turn one amp on or off pending on music i listen to..hehe