So, client wants to be able to hear what's on the Great Room's system in the Kitchen, which is within the same area (you can see the TV).
The idea is that you'll be able to easily (without any extra remote commands) listen to the TV (via volume control) without having to crank up the system in the Great Room and blasting out the Great Room.
Potential Equipment going in:
Yamaha Aventage 1050 (maybe the 2050, see below)
Fios (Frontier) stb
Apple TV
Possible bluray?
** I plan on using Yamahas Music Cast and feeding an amplifier to outdoor area, Living Room. AND Kitchen with zone 2 output. Each area will have a volume control. This presents the need for a/b switch in the Kitchen for the option to hear the Great Room or Zone 2, depending on HOW I get the Great Rooms audio feeds to the Kitchen.....
The Great Room will need to be able to stay on "surround sound" to decode whatever is playing correctly and sound right BUT at the same time feed the Kitchen as well.
Is this even possible, to get a stereo (or mono if need be) feed to the Kitchen without having to affect the main zone?
In looking at the 2050 Aventage, I see the possibility to use zone 3 or 4. I believe I can set the zone I use to main zone sync and it will always feed the Great Rooms audio to the Kitchen (via amp I'm assuming, I haven't done all the research), assuming I have that zone always turn on/ off with the main zone with macros.

"(via volume control)"? Which volume control? Something on the receiver? TV? In-wall control?

How would one switch the kitchen source "without any extra remote commands"? Are you proposing an in-wall line level selector switch in the kitchen?

One scheme would be to include an amplifier for the kitchen, selector switch, and an Audioengine attached to the TV's headphone output -- assuming that the headphone output exists and that it mutes the TV's speakers. Another scheme is using the stereo analog output from the cable box with the Audioengine -- but this would not include Apple TV and Blue-ray.

A concern in any case would be handling of the TV's audio output while watching a TV "App".

In my opinion, the "without any extra remote commands" makes this more difficult than it needs to be. Will you be using a unified remote, such as a URC, RTI, Logitech, etc.?

What would it cost to do just a dedicated DVC and VC off the mains (b) output?
I bet it would be not much compared the CF workaround.

TURN UP THE DAMN VOLUME!

You don't need an A/B switch. Music cast will take any source on the receiver and make it available at any other music cast location. Especially zone 2.

If I were really intent on doing this and the Yamaha did not have a two-channel output without delay issues between it and the main surround zone...

I'd make a little resistive summing device and mix the power amp outputs into stereo. Let's say all channels except the center have 100 ohm resistors in series with them to a summing point (left summing point and right summing point) and the center channel would have two 200 ohm resistors fed to both left and right. Each summing point then has a 2K resistor to ground. This is a crude but probably okay way to mix these channels.

Take this signal -- no delays -- and amplify it however you want. You WILL need an A/B switch.

I'm not sure if another approach that occurs to me will work. Will the Yamaha let you set Zone 2 to track the main zone, so switching main zone switches Zone 2 to the same thing? Some receivers used to do this. That would give you your second signal, the limitations of course being delays and whether you need an analog input for Zone 2 to work.

If the main zone is only 5.1, route the rear channels to Zone 2/kitchen speaks. I would loop through a keypad location and keep it buried. So they can add a keypad later when they realize they wish they had one.

I would use the 2050 over the 1050.
If memory serves me correctly, make use of the "Party Mode" and there shouldn't be any delays to zone 2.

Party mode is available on the RX-A750 and up.

RX-A1050 and above have HDMI audio extraction for zone 2 (with some video dropout during switching) and zone 2 audio delay. Adding some delay to zone 2 helps sync it up with the main surround zone.

This is exactly what I did for a customer years ago. Worked great. Rear speakers where on a VC. The used it when they wanted ,turnd it down when they didnt. Just make sure all settings are set to ALL CHANNEL and not dolby or other processing.

But what happens in that scenario if they want DD/DTS/anything other than 7Ch Stereo in the main room, and still want to hear it in the Kitchen? Or when a kid or someone pushes a button the AVR changing the sound processing away from 7Ch Stereo?

If you just want cable audio, put the kitchen speakers on a Sonos Connect Amp, with analog audio from the cable box the Sonos. The would have to use the app, but easy, and it works. We typically put a Sonos Connect on the AVR, and Connect Amps everywhere else. This wall all music can be matrixed throughout the system.

I'd ask the same question as your first one, but as to a kid or someone changing the sound mode, just program the sound mode into your macro in your control system. I do that anyway to ensure the system is always in the correct sound mode.

+1