What are your tone knobs set at on your channel on the board? Are they set in the middle? Did you try setting both your PA channel and the unit's eq to middle settings and then hear what that sounds like?...tweaking as you play with the group? Even readjusting your Digitech eq before it hits the board? Are you running it in stereo or mono? Any effects?
It would be cool if someone was playing your guitar with the group while you went past the speakers to listen to the sound. Anytime I've played through a PA...even miked I had to do that. Was never happy with my sound through a PA. Usually found that I had to do a couple of things on the board...
1. I always either set my board eq all to 12:00 straight up
2. Or I had to turn down my eqs to 10:00 or lower to help compensate for too loud of a signal boost on some frequencies. (usually I just adjusted my output on the amp and could hear myself through the PA anyway as an ambient tone).
Anytime you run direct to the board you're going to get a different tone. Yeah your sound is degrading. I could never get good enough line level signals going direct like that either. Maybe someone else has a good solution.
Guitars/Bass - MIM Fender Classic 50s Strat, MIM Fender Standard Strat, Squier Classic Vibe 50s Tele, Gibson Les Paul Studio, Epi '56 Gold Top Les Paul, Martin DSR acoustic, Sigma Martin Auditorium electric/acoustic, Squier Jazz Bass.
Amps/Cabinets/Modelers - Model 2558 50 watt Marshall Silver Anniversary Jubilee combo w/ Celestion Vintage 30s, 4x12 Marshall cabinet w/25 watt Greenback Celestions, Fender Blues Junior w/ a couple of Billm mods, Line 6 POD 2.0, Roland Micro Cube
Pedals/Effects - Cry Baby Classic Wah, Boss TU-2, Boss NS-2, Boss RC-2 Loop Station, Ross Compressor, MXR Micro Amp, Danelectro FAB Echo, Danelectro FAB Chorus, Danelectro Chicken Salad, Marshall Guv'nor Plus, Marshall Echohead, Duhvoodooman's Zonkin' Yellow Screamer, Digitech Digiverb, Digitech Bad Monkey, Dunlop Fuzz Face, Homemade Loop Bypass pedal, Duhvoodooman's Sonic Tonic (Maxon SD-9 clone +), Voodoo Labs Superfuzz