Im about 15...on 1 12 and clamping roughly 500w. peaking at 37hz. My roof flexes, my doors flex, windows flex etc. Actually knocked some stuff off shelves in my garage the other day with my car parked about 30 feet away from garage..Was told by someone with a mojo 10 that my bass in their car overpowered their bass //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif