On the front of the amp is a button that cycles between A-speakers, B-speakers, A+B speakers, and no speakers. I use B speakers for the ceiling speakers in the Bedroom and Bathroom, as well as the patio. This way, I can select to play music in my living room (7.1, Speaker A), or the rest of the house (stereo, Speaker B), or both. B-speakers need an amp, so you sacrifice the front height/front wide surround channels for it.
Just to clarify Zone 2: According to the manual (p28-29) there are two ways to achieve Zone 2 (playing a different componenth than zone 1):
1. You can use the "Zone 2 out" RCA plugs and a separate Amp like Krutsch described
2. You can also run zone 2 speakers directly from the surround back speaker terminals, but you will only be able to play 5.1 on zone 1 (since you sacrificed the surround back amps to play zone 2).
I wish that there would be an option in the setup to choose whether the Front wide/high terminals would function as Zone 1 or Zone 2, this way you could have Zone 2 while still using 7.1.... Maybe in the next firmware? Pioneer?