The parameters in the ES1 Amplifier section allow you to fine-tune sound level behavior. These are separate from the global Out Level parameter, which acts as the ES1 master volume control. See ES1 global parameters.
Level via Vel slider: Determine how note velocity affects the synthesizer level. The greater the distance between the arrows (indicated by the blue bar), the more the volume is affected by incoming velocity messages.
Drag the upper arrow to set the level when you play hard (velocity=127).
Drag the lower arrow to set the level when you play softly (velocity=1).
To simultaneously adjust the modulation range and intensity, drag the blue bar—between the arrows—and move both arrows at once.
Amplifier envelope selector buttons: Determine the ADSR envelope generator used for control of the amplifier envelope. See ES1 envelope parameters overview.