I've used the HD500 direct into our sanctuary’s PA for more than a year with excellent results. When I started out, I spent a few weeks fine tuning and tweaking settings – setting EQ, and adding delay, reverb and chorus effects (used sparingly). I also use the built-in expression pedal as a volume pedal so I can easily adjust sound between pieces or when moving between finger picking and strumming.
I've only played my acoustic, but will play electric with the HD500 for the first time this Sunday. I'm eager to hear how it sounds with amp models and a bit of crunch.
