Yamaha MU90R Owner's Manual page 52

Volume
This determines the Volume setting for the selected Part's Voice.
Expression (Expresn)
This determines the Expression setting for the selected Part's Voice.
Pan
This determines the stereo position of the selected Part's Voice. A set-
ting of "Rnd" (Random) randomly assigns the Voice to a pan position.
This is useful when you want to have different Voices sound from dif-
ferent random parts of the stereo image. (The Random setting does not
affect the A/D input Parts.)
Graphically indicates current Volume setting.
Graphically indicates current Expression setting.
Graphically indicates current Pan setting.
MULTI MODE
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