Quote Originally Posted by anna1984
ive got a 12 at d moment but wud like an upgrade to 2x 12inch or jus the one 15..
wot would you recommend??
Remember good quality (including loud but listenable) sound is all about enclosure design and power, NOT cone area. I can blur vision with a single 8" driver (and do regularly to prove a point to customers here). Anna, a single 12 is more than enough. If you don't have enough bass, get a better subwoober (eg IDMAX12) and a large amplifier.

Another common misconception is that large subs are only good for SPL. This is untrue as well. If your amplifier has the power to control the cone it doesn't matter what size the subwoofer is.