Steve, What do you recommend?

[Omega5002]

^{Yeah, just do a simple ported or sealed box, and to access the spare tire, he can just remove the box if needed.}

[Cazz]

A big box in the boot would be no good because he would have to take it out to do the shopping once a week which would be a pain. The whole system was professionally fitted and the sub in the boot is bridged to the amp which is bolted to the back of the seats which is directly behind it. He was also thinking is he was to put another sub at an angle to eachother so that he could still do the shopping and wire them to the amp, left and right channel would that be better then one bridged. This might sound stupid but we know nothing about car audio we just love bass.

Also what is pups?

[Cazz]

[Trey_Dog650]

not too sure hes going to get the sound he wants with those restrictions...

[sayhuh?]

Hey Steve

I was wondering what you would recommend. My dad wants to upgrade the bass in his car since he has watched some of your videos on youtube. He has a BMW E36 M3 3.2 Evo, with 2x Alpine SPX-13REF in the Footwells, a Shallow Rockford Fosgate PS3 Subwoofer connected to a Rockford Fosgate P300 Amplifier in the boot, Original Rear Speakers still in car. He wants to add 2x 12" Subwoofers on the back shelf but is not sure if he can bridge all 3 subs with the Alpine CDA-9887R Head Unit that he has, also he wants to put 2x Alpine SPX-13REF in the rear doors and connect them all to one Amp. Any recommendations would be much appreciated.

[Omega5002]

If he doesn't want a big box, just get smaller subs, size of the sub doesn't determine the deepness of bass.

[Cazz]

The restrictions in the boot is the reason why he wants to put then on the rear shelf, but should he get 2 more amps for each sub or is there a way to use one amp for all 3 or 2 subs. Please give some ideas, would he need to upgrade his head unit to have the extra subs?

[Cazz]

Ok so we have a idea to remove the Original Rear Speakers that are on the back shelf out, with the holes where they used to be could be made into a air hole. If we were to put a sub next to it we could seal off the bottom and use that as the air hole for it. and also if we put 2x Alpine SPX-13REF in the rear doors we would put a amp under the passenger seat to power the front 2 and rear 2 Alpine speakers, then either use 2 or 1 amp to power the subs on the rear shelf. If this idea is not good please give us some ideas. We dont really want to put any more subs in the boot so that my dad can access his spare tyre and have room for the shopping. Also recommend some good amps and subs please. Any ideas would help alot.

[Crandis16]

The way I see it is you want bass with no box right? That makes things a little more difficult. You can do a build where you essentially use the trunk as the sub box, the problem with that is that it take a "free-air" subwoofer, not any type of sub. You also have to make sure that your trunk is very air tight to the rest of the car which can be difficult.

I suggest running a couple SA-8 v2's in a box in the trunk, it won't take up a lot of space and they are some vicious monsters

Edit: 2 SA-8s in a box will be 1-1.5 cubes ported and .56 cubes sealed, that still leaves a lot of room for groceries and taking the tire out of your boot at the same time

[Cazz]

Would we be able to put a sub on the rear shelf but seal the bottom off so there would be a box attached underneath it with a air whole next to the sub? Also are these subs better then a Rockford Fosgate PS3 and what amp should i use to power these? Would i need to upgrade my head unit?