I didn't think that was actually considered a genre. Learn something new every day, I guess.
Pipe organ doesnt have particular overtones. Say I played a jazz organ song on an organ with a different timbre, or even worse...a tine instrument...they have such different tendencies. You could hear more dissonance of the same song on one instrument, yet not the other(but the jazz organ really was masking a lot of dissonance from the chords that were very large and complex). Likewise, a less complex instrument could not turn dissonance into harmony and make music out of pure tones....hmmm