how is 150+ db off a PAIR of 15s with 2000rms in a prefab box for under $500 not heavy bass?? have you heard any of the new quantum alpha series stuff... for the price tag, its honestly hard to beat! if you watch it long enough you can get something with true watts with the price tag of boss... to me thats a good deal. Ill get a few more of them and strap another just diamond d5 to them and let you hear them... you'd be surprised.. guaranteed. The orange and black quantum stuff is garbage i know this, but the alpha series is not bad, sells like crazy around here. I'm running mine at 870wrms daily and have been for over 6 months and it doesnt stink or even get hot.. warm yes but not hot! its in a 4 cu/ft box tuned to 32 hz.. almost twice the box size it recommends from quantum and i've had no problems, nor has the other 10 vehicles ive put the new quantum stuff into.
If he wants *HEAVY BASS!!* look for like a pair of DC lvl 4s and hope you can find them cheap enough used. with the quantums he could basically almost build a whole system for under $500... if he has a limit of 500 then he's not going for all out competition status. probably just a hard street vehicle, and those quantums would do it guaranteed with a small price tag