Community,

I ordered a set of XLR3M to 1/4 inch TRS (Balanced) adapters to gain XLR connectivity out the back panel outputs. Rather than try to determine if they'd fit beforehand, I just ordered a few and took the risk. I'm happy to report that they fit, side-by-side, with XLR(F) standard mic cables plugged into them. There's about a 2mm air-gap between the connectors - plenty of space. The downside is how long the two connectors extend out the back which is a lot of potential/it-is-a-lever energy for breaking your output if there's a mishap (someone is falling and uses the connectors to keep upright). Cables have right-angle 1/4 inch TRS - maybe there's an adapter that presents the XLR at a right angle which would decrease the lever effect and generally be a tidier configuration.

I used 2x Hosa GXP-246 connectors which are mid-range. You can spend more or less - Hosa is a good balance. The main point is that most anything should fit because the connectors are properly spaced apart by Yamaha.