oh and just for the hell of it...
if you are into EROTIC car stereo bass...
http://www.ddaudio.com/caraudio/woof...p?series=9900b
QUAD!! Stacked 3in voice coils, 300oz magnet, 5layer kevlar cone, 1500/3000 watt power handling 17" woofers...
only one problem, MSRP, 1299.00$
but THOSE are the SPL leaders of the pack.. you haven't heard ANYTHING until you hear one of those... holy shit...
one guy from south africa, 3 DD 15" woofers:
1st Martin Byrne (After-Byrne Audio)
('56 Mini Wagon) 3 x DD 9915Q2
12 x U.S.Amps 2000X 172.9db (New World Record)