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When morphing between scenes, if the two scenes aren't tuned the same, 
like one scene is an octave higher than the other, then when you morph 
the sound goes out of tune pretty horribly and then back into tune. 

This works well for hard rock tunes where you hit mostly chords and 
move the wheel when you want an especially dicordant chord. Works nice 
for leads too.

If you want a more subtle effect, keep both scenes tuned the same, then 
as you rock the mod wheel, you get nice changes in timbre in time with 
the music.

Jimmy