Originally Posted by canbonbon
Lets say I connect 3 CCAs (X, Y, Z) to the 3 inputs (DVD, CD and AUX - all Analog)..
You wouldn't use those inputs, as that won't work. You need a receiver model with a single multi-channel input. This will have 8 analog terminals, corresponding to each of the 7.1 speakers. You need to check the specific model name, google it, and look at the image on the back.
A quick google image search for "multi-channel input" yielded plenty of results. For example :
In this model, the multi-channel is labeled "EXT IN".
You can use one CCA on the FL/FR terminals of the "EXT IN". (front rear/front left), and then its output will play on the 2 speakers attached to the "front A" terminals (do not use "front B" as that will likely disable some of the other channels on the receiver's amp).
Then attach the second CCA to the "SL/SR" terminals of the EXT IN, and then its output will play on the 2 speakers attached to the "surround" terminals.
Then attach the third CCA to the "SBL/SBR" terminals of the EXT IN, and then its output will play on the 2 speakers attached to the "surround back" terminals.
You are left with 2 more inputs on the receiver's EXT IN. You can't use the subwoofer terminal because it's not amplified. You probably can't use the center terminal either, unless you want one zone to be mono.
If you want to expand later and use a second AVR with an EXT IN, you could use two of the CENTER terminals together and hook up one CCA's left channel to the AVR A's CENTER on the EXT IN, and the CCA's right channel to the AVR A's CENTER on the EXT IN. You would have to calibrate the volume between the two AVRs though, which could be painful if they are not the exact same model of AVR. I don't have 2 identical AVRs in my home, and I have a lot of them. So I leave the CENTER terminals alone when amplifying the CCAs.
I am using a bunch of AVRs like the above in my home to amplify all my CCAs. 3 AVRs on one floor, and 3 more AVRs on another floor, since I have two locations for the feed. Some of the AVRs are 5.1 and can only power 2 CCAs each. Some are 7.1 and can power 3 CCAs each. I'm not using the CENTER channels for anything. In fact, I bought one used AVR with a broken CENTER speaker terminal for very cheap, since I knew I wasn't going to need that channel ...
If you just have 3 CCAs, a single 7.1 AVR should do the trick. You just have to find an old one that has a multi-channel input. There are some like the above that do have both HDMI and multi-channel external inputs. There was a transition periods. Many devices like SACD players only had RCA analog outs, and no HDMI out. I still have some of those.