Main LR output mono?

right now I have my main LR output feeding 2 separate channels of an amp to my center cluster of speakers. I would like to be able to pan instruments L and R but still have my center cluster be mono… Would I need to utilize say mix 9-10 and just set all the faders to unity, and have them all be post fade from the main mix? I suppose the other way would be an outboard item that takes the stereo mix, and makes it mono…?

If I use mix 9-10, I could pan the mics differently from how they are panned on the main mix right?

Jay…

Use Alt Out and select L+R as the source/config to feed the center. The level will follow the mains fader but you also have an Alt Out trim pot for tweaks.

Or use matrix out if your desk has it.