I have Bose AM6 speakers running through Denon 1801 receiver. I have read lots of threads about Bose, mostly bad, but I have had them for a year now and taking into account size, etc, I am very happy. I upgraded from Videologic all-in-one system and the difference was immediately noticeable. Anyway, the only thing I am unhappy with is the Accoustimass unit. Can I add a separate sub to my system? Will I be able to run it alongside the Accoustimass or separately? Any recommendations for a good sub or does anyone have one for sale? REL seem v good bit as I don't get to use the system as much as i'd like (due to neighbours, girlfriend and son!) I don't want to break the bank.