Yamaha RX21 - Manual (Page 23)

IMPORTANT:
If you switch from a higher quantize rate to a lower one, only the notes occuring
on the new beats will remain-all other notes will be cleared. For example, if
you have programmed a part at a quantize rate of 1/32, the Beat Exchange
function will switch the quantize rate to 1/16, and all notes which originally
appeared on beats 2, 4, 6, 8 etc. will be erased. This will affect all instruments
simultaneously.
Let’s look at what happens to a 2/4 time hi-hat pattern, programmed at 1/32 quantize
rate, when we perform the Beat Exchange function.
QUANTIZE AT 1/32
BEAT EXCHANGE TO 1/16
All the notes originally occurring on even-numbered beats have gone-permanently.
It is safer, then, to use the Beat Exchange function for switching from a lower
quantize rate to a higher one, so that you can add rhythmic subtleties rather than
remove them.
Beat Exchange (Example: on pattern 00)
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