Korg M3 Parameter Manual page 309

Sampling Overview
Note: Changing velocity on the keyboard or pads
In Sampling mode, you cannot use keyboard or pad velocity
(with PAD MODE set to VELOCITY SENSITIVE) to control
the loudness of the sound. However, you will be able to use
velocity to control effects if you select Velocity as a Dmod
Source.
For example, you might make settings as follows.
Bus (IFX/ Output) Select: IFX1 (P8 IFX: Routing)
IFX1: 002: Stereo Limiter, On (P8 IFX: IFX)
Stereo Limiter:
Ratio 1.0: 1
Gain Adjust [dB] –Inf
Source Velocity or Exp Velocity
Amt (Amount) +40
If you are converting a user multisample into a program for
use in Program mode, you can raise the Prog P4: Amp/EQ,
Velocity Intensity value as desired to control the sound.
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