Yamaha MU50 Owner's Manual page 56

This determines the Attack Time of the EG, or how long it takes for
the sound to reach full volume when a note is played. For the Filter,
this determines how long it takes for the sound to be affected by the
maximum Filter values.
Graphically shows EG Decay Time setting for each Part.
Selected Part and MIDI channel
This determines the Decay Time of the EG, or how rapidly the
sound dies out as a note is held. For the Filter, this determines how
long it takes for the Filter effect to die out.
Graphically shows EG Release Time setting for each Part.
Selected Part and MIDI channel
This determines the Release Time of the EG, or how long the sound
sustains after a note is released. For the Filter, this determines how
long the Filter effect continues after a note is released.
MULTI MODE
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