I do that quite a bit at church. I frequently have someone fill in tymp parts to majestic hymns along with pipe organ and grand piano and sometimes brass. I'll also have someone do brass parts on another board when I don't have real brass players. For Easter this year we did a cantata that was mostly rockin praise music. For this kind of thing I usually bring in my old band guys. Money was tight this year so I set everything up on my Yamaha PSR 900 along with piano and my little string ensemble and flute. It worked beautifully. People were clapping along from beginning to end. Keyboards are an amazing thing.

Joe