Not exactly...
I was talking about running the xtl direct to the mixer, anything that goes through the mixer will sound piercing, and your lows and mids might be gone, so paying extra attention to the treble is always a must while playing through the house mixer, bump up your lows and mids if there's a need to.
If I do play through an amp, I'll try to get a usable sound by tweaking the eq on the amp. Never really liked to rely on the effects loop, I've had my fair share of non-working effects loop.
Find a patch you like, and tweak it yourself, you'll learn quite some stuff in the process.