I've used the search function already, and there were a few helpful threads. here's my dilemma, i was playing at church on Sunday(as i do every sunday) and i noticed that from the low E to the low B, there was no 'presence'. i mean, i could hear the notes, but they didn't sound the same as from the F upwards. this could be due to the markbass, but from F up, you can really FEEL the notes. i want that for the lower register also, and after a LOT of thought, i'm thinking that bass cabs are probably not designed to give that sort of presence. i'm thinking that a powered sub is the way to go. i mean, home theatre, cinema, and car audio use dedicated subs for the ultra low frequencies, why shouldn't i? after all, i am the BASS player? so i want to find out from the guys that use subs: i- what size drivers do you guys use? ii- what crossovers do you use? iii- how has the sub improved/detracted from your sound? etc etc thanks a lot guys.