You mention: 861v6, Sooloos Card [ID40], C15, MC200, MS600 and DSPs. However, as I think you suspect, you don't need all of this kit for a two zone system.


The ID40 Card in the 861v6 is one zone.
The digital audio (SpeakerLink / SPDIF) out the back of the C15 is another zone.

Each zone can have independent output, which can be selected via the C15, ControlPC (which also adds another zone), iPad, iTouch, iPhone.

For the best audio quality use C15 to 861v6+ID40 via LAN.

Thus a two zone system would look a little like this:

C15 --LAN--> 861v6+ID40 --> DSPs
.... --SpeakerLink---------> DSPs


Regards,
Carl

861v6+ID40, HD621, 8000.2, 7200HC, 7200.2, SKYQ Silver, PS3, PDP-LX6090, QNAP TS870-Pro (8*6TB), Roon, iPadAir2.
[In Reserve] C15, MD600 (2*3TB), TwinStore RM (2*2TB)