Yamaha PLG150-DX Owner's Manual page 33

Soft2
This curve also produces greater volume in the soft velocity range,
but is less pronounced than "Soft1" above.
Easy
This curve also produces greater volume in the soft velocity range,
but results in a more consistent, stable response throughout the
entire velocity range than the other "Soft" curves .
Wide
This curve decreases the volume for softer velocities and increases
it for stronger velocities, resulting in a wider dynamic range overall.
Hard
Compared to "Normal," this curve produces greater volume in the
hard (strong) velocity range, making it suitable for players having a
heavy touch.
Parameters
Volume
Playing strength
Volume
Playing strength
Volume
Playing strength
Volume
Playing strength
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