Sony P5 12" Subs and a little Autotech Street Machine Amp. I bet that is quite loud considering how much you paid :P
I've had pretty good luck with the p5. I'm not a fan of Sony +12volt audio, but those little subs sound pretty good and don't blow up real easily. You should be good, with a clean signal from that Autotech Amp...
Everything they did was so clean, I didn't directly buy any of the equipment for the installation so I don't know where the wire taps came from but they are very nice! I really like how BMW leaves some empty spaces in that battery connector box, makes it really nice. My amp is coming this monday, I am usually slow about installing things like that so I would say by the following thursday I'll have it installed and I'll take pics. Oh yea, and if free subs arn't good enough, because the company that I bought the amp from (woofersect.com) was so late in shipping it out, they gave me free speakers for inside my car. However, they didn't tell me the brand of anything, so they might suck and the BMW stock speakers are pretty good. For now.....
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