Yamaha PSR-9000 Owner's Manual page 138

The PSR-9000 "Functions"
TRANSPOSE ASSIGN
This determines the function of the [KEYBOARD TRANSPOSE] buttons.
KEYBOARD TRANSPOSE
RESET
When set to "KEYBOARD" (default), the buttons transpose only the keyboard sound.
When set to "SONG," the buttons transpose only the song playback.
When set to "MASTER," the buttons transpose the overall pitch of the PSR-9000.
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