Re: Help putting playback system together, please.
Sean,
I read the Cliffs Notes only prior to my post. Now that I've gone back and read everything on the other site...
I pointed out that Denon unit because that would allow you to take all 6/7/8 channels (albeit analog) into the console on balanced lines and do your own redistribution of content. HOWEVER, Brad raises some excellent points that, until I read the rest of your post on the other site, I didn't see exactly what you were getting at.
Question #1: What exactly are you trying to accomplish with this setup?
You won't find anything in a manual about '3.1 audio' because it's not a real format - it doesn't exist. At best, you may find something about 2.1, but if someone is going to the trouble to encode a multichannel mix that includes discrete center and/or surround tracks (at worst, Dolby PL or PLII), you'd still have a base level Lt/Rt mix that could be played back on a simple set of stereo loudspeakers, no decoder necessary. The fact that your system (for cinema purposes) is likely bass managed as far as the subs are concerned, means you probably don't have a discrete sub input. You could be running subs on an aux, but I won't even get into bass management/bass redirection at the moment.
Question #2: How's your center channel coverage - does it cover every seat in the venue? No? Then you're already running down the wrong path trying to do discrete screen channels.
My point in all of this is that clearly you're doing more multimedia/interactive events and less cinema, which is perfectly fine. But if you plan on using cinematic content, you either need to play by some of the industry conventions with regards to loudspeaker coverage and audio formats, or be prepared to take the decoded 6/7/8 channels of audio and redistribute them to your liking as per the requirements of your event. If you already have a means to extract the multichannel audio (which it sounds like you do), then your best bet to do what you want is burn a bunch of channels to get that into the console and do a couple creative matrix mixes to get it where you need.
