Roland M-GS64 Owner's Manual page 13

® Reverb (Master Reverb Level) : 0 - 127
This sets the depth of the reverb effect for the entire M-GS64.
: Off, Vol, Hold, On
This sets the reception status for volume messages and hold mes-
sages independently for each Part.
received.
: On/Off
This parameter sets the reception status for Program Change
messages independently for each Part. When this is turned "on,"
Program Change messages will be received. When this is turned
"OFF," they will not be received.
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