My solution for last night was to team the Yamaha with the Spacestion and a Z2200 Logitech sub I had, and VOILA, what a sound.
Bernie ... I still have a Z5500 which is getting NO use, but I am interested in how you 'wired up' the Z2200 and the SS ... I may want to try the Z5500 sub for a couple of larger gigs I have coming up ...
thanks