Hello............Recently I've been playing some GS midi files on my Tyros2. The Tyros2 plays them using its GS soundbank. When I play other midi files the Tyros can substitute its panel voices if checked. Why don't GS files allow this option? I've run them thru Michael's MidiPlayer and it can convert them with it. How is a GS midi file differ in structure from a Yamaha type 0 one? thanks. -charley