all great information guys, you covered alot, but lets cover the best way to use a sub in it's hook up. If its a active or passive xover would play a part, but also makes a difference if it's self amplified or requires outside source amplication. I would assume that if it is self applied amplification, you would only need to hook to the preamp, but if you are using a stereo preamp and are using one sub how do you work around that, left channel right channel combined into one sub? and if a non powered sub, if you don't have an alternate amp laying around, whats the workaround for that? just excercising the cranium...