I have a Bose Acoustimass speakers ( a gift not a choice purchase)hooked up to an Onkyo rec. for secondary HT system in my basement. I am not pleased at all with the bass from the Bose sub and was wondering if I can replace it with another sub? Someone mentioned the Bose systems are integrated and may not be compatible. Could someone shed some light on this? Also, what sub would you recommend for a 14 x 18 room? I have an Infinity Alpha 1200s in my primary setup and it's a very good sub. But I wanted to try something a bit tighter and a bit less boomy.