Thank you!! This helps a lot.There are gain knobs for center and surround channels individually. Set their level by ear relative to the L and R channels. The beauty of Syn is in the simplicity!
I set the levels with processing (width and presence) disabled, and then use the width and presence knobs as needed. Once overall levels are set I don't touch them much at all. I only rarely use processing for programs that need it, like the F1 racing example I mentioned above.
When listening to music with all channels active, I usually attenuate the subwoofer and center channels a bit. For TV and movies I have like to have the center and sub turned up higher for clearer dialog and low frequency effects.
Enjoy your Syn when you get it!! My advice above really only relates to 3.1 or 5.1 setups. I haven't really used it for 2-channel only, but I'm sure it will work out great.
I am switching to monoblocks for my LR and since I want to build a 5.1 system and get a Syn eventually, getting it early and use it as a preamp for the time being. Will be interesting to see if I can get anything extra out of it as it sends full signal to LR channels.
Will share more here once I have a chance to play with it for a bit.