For the last 10 years or longer Integra has had main and zone2 with supporting digitial/analog input to main and analog input on zone2 and supporting preouts for both main and zone2 - newer models adding sub out for zone2 and also adding zone3 and zone4, also adding Master HD and HDMI.
I use my dtr-6.4 for main 5.1 and zone2 2.0 music and wanted to replace the dtr-6.4 with an integra like the dtr-6.6 for the zone2 sub preout to make zone2 2.1
Now, I am thinking of keeping the dtr-6.4 and connecting it to the dtr-6.6 and having a 5.1 and 3.1 (or just two 3.1) systems and using the two on occasion to play the same source.
I have thought about two options for playing the same source and I think splitting the input signal may be a better choice vs ganging the two receivers together. Actually both approaches would require splitting signal.
I wonder what the options are Choces in terms of cost and quality between a Y cable and maybe a need for a ground loop isolator cable and a $250 Henry Engineering Matchbox.
Music and HT have different issues for Integra and my setup
I input HDMI straight from source to the TV and take optical out from the TV to Video3 SPID input on the Integra. This will plays on main 5.1 and can be selected on zone2 if main is selecting it as well - as 2.0 (or 2.1 with the dtr-6.6). Normally this just goes to main - again note it has to be on main for zone2 to get it.
I input Analog music source to Integra CD input. This plays on Main or zone2 or both as desired independantly.
These vintage Integras are before HDMI was supported so the DVD input is the only analog 5.1 input.
From my HTPC i use analog and ground loop isolator
If I connect the two receivers together conventionally then would use the main 5.1 Preouts from the first recever to the DVD inputs on the second receiver.
The immediate consequence of that is no preout for the main system to another amp, notably the main subwoofer.
So I need to split the preout from the first receiver, at least for the main subwoofer and for any other speakers that I may want a separate amp for. What to use for the split? A simple Y cable?
For what it's worth all the gear less than 10' signal cables plugged into the same power circuit want to avoid unbalanced/balanced input being key to this since that means to me the Henry box.