There is not a traditional 'speaker B' or 'zone 2' output from the 650R, but there are a couple of options available;
1. There are two Incognito multi-room outputs from the 650R effectively giving a second and third zone.
These wire with CAT5 from the 650R to an Incognito keypad in the second and/or third room(s), which then, in turn, powers a small pair of connected speakers/ceiling speakers.
This will allow a different source to be listened to through the keypad speakers than is playing in the main room and also for the keypads to be switched on or off independantly to the 650R.
2. If you have speaker cable wired back from a second room to the 650R, then you could connect the 'surround back left and right' speaker connections to run a pair of speakers in a second room.
Then, to make these work, yoou would need to go into the 650R's OSD and in the 'speaker configuration' page, enable the bi-amp option.
Then the front left and right speakers channels will effectively be 'copied' and sent out of these additional outputs (normally intended for bi-amping the front speakers).
This will effectively give you a 'speaker B' setup in the second room. As this is simply 'copying' whatever is playing through the front speakers in the main room, the same source and volume level will be heard in both rooms.
Please note if using this latter option, as there is not traditional 'speaker B' switch, the only way to switch on or off the second pair of speakers will be to enter the 650R's OSD each time and turn on/off the bi-amp option.