This may be a stupid question, but I can't figure it out looking at the specs. Does anybody know if any (maybe all) of these receivers has amplified output for subwoofer? In other words, can I just plug in a non-powered sub to them? Denon AVR-1802 Denon AVR-2802 Onkyo TX-DS595 Onkyo TX-DS696 Onkyo TX-SR600 Thanks for your help!!!