I am just starting to add some canned music to my performances. I play guitar and sing, and would like to add some tracts or take some out? If I download a midi file from the internet, can I make one with all of the instruments, and one with the bass out? My son and I play and he plays the bass, and would like to drop the bass line, or if someone is playing lead guitar can I take that tract out in real band. Also I saw a duo last Friday night and they were using a foot pedal for volume control. They were using 3-1/2 discs in a key board for the midi? I would like to use my computer and work up a whole set with a whole band just for single work and another set with out the bass so my son can pick along?? Any info will be helpful.