I read the Rane article. I wasn't aware the lack of stereo separation wouldn't be very noticeable. This is a very big garage so that won't be too big of a deal anyway. Loud and clear is more important.
The source is Zone 2 unbalanced from a Marantz preamp.
The amps will be balanced with the front panel level controls and the master volume is controlled from the preamp. Cross over will likely be at 80hz.
I have never gone unbalanced into the CDi. A long time ago 3peddlemini said he used to go unbalanced in but started using the cleanbox pro to convert to balanced and heard an improvemt in sound quality. For $60 I figured why not.
You recommend replacing the 470 ohm resisters with 1k? Leave the 10k as is?
My wife says I can't do sarcasm. She says I just sound like an a$$hole.