Yamaha SY99 Owner's Manual page 18

7. When the data is loaded, the SONG LED will light red, and a display like the
following will appear. Press RUN to begin the playback.
To listen to the demo songs contained in another demo disk, repeat the above
procedure.
Note:
The voices contained in the SY99's internal memory are replaced by other
data when you load data from either of the demo song files. You can restore
the internal voices by loading the file named "INTVOICE" from the "Chick
Corea" demo disk. To do this, use the load procedure described above,
selecting 02:Synth all instead of 01:All data in Step 4.
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