Yamaha DGT7A Basic Operation Manual page 62

You can choose from the following options.
Option Description
## The piano does not play.
01 - 16 The piano plays the specified
track.
Prg The piano plays the smallest track
that contains a piano group voice.
Prg(all) The piano plays all tracks that
contain a piano group voice.
The number of the chosen track appears
next to L= or R=, and the
across the display, to indicate which track
the Disklavier GranTouch will play.
Note: Changes made above are temporary
and are valid only during playback. To
make permanent changes, see Chapter
8 "Editing Tracks" in the Advanced
Operation Manual.
50
symbol moves