I guess this is the mystic "spread" feature.
Manual says:
If there are 4 or less notes being
played they will always be stacked in thirds. Otherwise there are 5 settings,:
1) stacked by thirds,
2) root only in bass octaves, open voicing in mid-low octaves, closed voicing in mid-high octaves,
& root only in high octaves,
3) root only in bass octaves and closed voicing in 4th octave,
4) 70%
chance for any Pad note to be played,
5) root only in bass octaves, root and 5ths above, 6) root
only in bass octaves, 3rds or 7ths above.
Manual says:
If there are 4 or less notes being
played they will always be stacked in thirds. Otherwise there are 5 settings,:
1) stacked by thirds,
2) root only in bass octaves, open voicing in mid-low octaves, closed voicing in mid-high octaves,
& root only in high octaves,
3) root only in bass octaves and closed voicing in 4th octave,
4) 70%
chance for any Pad note to be played,
5) root only in bass octaves, root and 5ths above, 6) root
only in bass octaves, 3rds or 7ths above.