2 15's or 4 12's

i have an problem here. im doing my friends install and he is trying to choose between two audiobahn 1500q or 4 audiobahn 1200q. Now he is set on audiobahn and since its his money i cant tell him how to spend it only offer advice. he also is gonna choose between the 4 alum12q and the 2 alum15q. Now they are going in an 71 cutluss. ANd he is only gonna use 1 jbl1200bp.1 amp and he wants me to wire the subs down to 2 ohms which wont be a problem cause he only plans on buying 4 ohm dvc. Okay the enclosure will be an enclosure for 4 12's each with their own chamber with 1.37 cubic feet per sub. While the 15 enclosure if he decides on that will be 2.4 cubic feet per sub. Im guessing the 2 15's will be louder and better matched with the amp then 4 12's that would be underpowered badly right. So what should he go with 4 12''s or 2 15's and which model will be louder. Loud means spl with him. please post cause he listens to this forum alot......................goingcrazyonsound

This is a not so simple problem. If he is using two dual voice coil 15's and they are 4 ohm coils than two ohm mono is not a possible wiring configuration only 16 ohm, 4 ohm and 1 ohm mono configurations are possible. You can wire in stereo but your results would still come out to the same power configureation as the previously stated loads. I however also agree that the 4 12's would also be underpowered by that amp. I also believe that if properly powered the 4 12 would curb stomp those 15's for spl. There's no replacement for displacement. That JBL amp can run one ohm mono so he could use it to run the two 15's, or get the 4 12's in a dual voice coil format and use two amps, each wired down to one ohm and a chambered box to go in the trunk. Those are my best two suggestions without deviating from the first plan too much. If he wants the loudest possible set up then get a second amp and the 4 12's, if he wants to avoid the extra cost then do the 15'sdouble-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer

thats what i been trying to tell him but he says audiobahn overates their subs so he would be alright but i know audiobahn overates but these are not entry level subs so he cant get away with that especially since he wants the alum series or the q series. i had audiobahn before and i no longer want it but i have heard the alum series and they are decent subs if you can get them 2 for 1 on ebay.goingcrazyonsound

I would go with the 12s personally because I had 15s...they were Pioneer tho....and they dont sound as good as 12s. They hit too low.

he is gonna make up his mind by friday and hopefully he pics the 12'sgoingcrazyonsound

The system should sound good with either size, at least your friend didnt get audiobahn amps as well. I know a guy who has one audiobahn 15" in his escort, its the top of the line sub and it destroys systems with 2,4, or even 6 12" subs!!. I have also heard many systems with 2-4 12" audiobahns, they get very loud, even with two 12s...as long as you dont match them up with a horridly overrated audiobahn amp.