ok today i got my 18" RD audio sonance in and i listen to it for about a hour or so. this is sub is great. i have heard the 18" fi q and now this one and all i can is that sonance sounds better and is louder then the q and the sonance is in a sealed box. the sonance take less room to run in unlike the q witch takes 6-10 cubs the sonance only needs 4-8 cubs. all around this sub is a good sql sub. it hits every note on country and rock but it still can handle the low note such as late nite tip. i would recomend this sub to everyone that is looking for a good sub. i have mine powered by a rd audio 1000.1 witch was on the fi q.