Thanks for the replies

Quote:

See if there isn't a setting in the piano menu somewhere that sets the output to Mono. OR - Many pianos default to Mono output when using only the L audio output plug. Check the manual for the piano.
--Mac



Yes, I get mono if I use just the L output from the keyboard but that doesn't make the piano sound any better when plugged into the mixer mono. However one of the piano voices is called "mono piano" and described in the manual as "good for ensemble performance" I had been ignoring this voice because I didn't like it's piano sound however when I use it there is no longer any difference in the sound between using the mixer stereo or mono inputs so you are on to something. Why would it sound better using a mono piano sound rather than a stereo piano and just combining the left and right at the mixer mono input plug?

I may have to choose between using the "mono piano" through the EQ or my prefered stereo piano and accepting the bass level which is the only thing that is bothering me. Perhaps the Bose will sound better when I can crank it up on stage. I plan to do some sound checks.

Quote:

how does the bose sound if the Yamaha CP33 keyboard & computer are plugged directly into it?




The computer and synth stereo inputs always sound the same which ever route I take.
If I plug a stereo piano sound from keyboard to Bose it sounds the same as going through the mixer stereo inputs i.e. better than going through the mixer mono input.