unless the board is too hot and you need to knock down the signal a bit.
Which is very likely...the XLR output likely runs at "pro" level...much hotter than what a RCA "consumer" input is expecting to see. Unless you can control the output level at the XLRs - you may be taking a risk of brickwalling the RCA input...
I think Pro gear is +4db
Consumer -10db
Is that right? I forget...
Yeah, that's about right. Absent the "adapter phobia", I carry a set of Whirlwind XLR "Y" cables (2 female/1 male) and a pair male-2-male barrel adapters - so I can patch anything to anything. All my gear (v3 & D10 Pro) is either pro, or jumper adaptable, so input levels aren't a problem (never brickwalled the V3 anyway - I don't know that you actually CAN). SBD outs may frequently be 1/4 Phone also, or you may have to "rob" signal from an insert on the master out (used for EQ's, compressors, etc. that are pre-master-faders - insert tip/ring connector 1/2-way).
When I'm heading out for a board patch I carry my "magic bag" which contains:
2 - Whirlwind XLR "Y" cables - 2F/1M
2 - XLR M-M Barrel Connectors
2 - Direct Wired (no impedance matcher) RCA-M to XLR-M
2 - RCA-F to 1/4 Phone Adapters (the kind that just plug onto RCA males)
1 - mini-stereo to RCA cable (in case I gotta run out of the Sound Guys D-8)
2 - Gold RCA-F Barrel Connectors
There basically isn't a console you can't get a line out of with this assortment. Most will be just a plain pair of XLR mic cables required. While yes, you want as little as possible in your signal path, unless you're patching Phish or The Dead - there's likely gonna be so many junk cables onstage, and FX patch's on the console - that a couple more connectors between the console on your pre/deck aren't gonna make it any worse (and I've seen some pretty ragged out consoles in clubs).
Typical "patchers courtesy" applies also. Soundguy is likely busy, band soundguy (unless it's thier own rig) likely doesn't know WHERE the patchpoints are on that particular console anyway. Ask the HOUSE engineer, if the band is OK with patching. Ask what type of connection is required, get your cables/adapters ready, and stand back until he's ready to plug you in, then get out of the way.
Rick