Yamaha MONTAGE M6 Operation Manual page 396

Voltage Drift
Specifies the pitch of the Oscillator and variation of Filter Cutoff.
Oscillator pitch and variation of Filter Cutoff are affected by Ageing.
Settings: 0–127
0: No variation
64: Standard
127: Maximum variation
Ageing
Adjusts the frequency response as well as OSC Pitch, Filter Cutoff, and EG Time according to
the virtual age of the instrument model.
Settings: −100 (old)–+100 (new)
Correlation between Voltage Drift and Ageing
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