As shown by the modulation source select switches for VCOs 1 & 2, and the VCF, the shape of ENV1 can be used to modulate VCO1 and the shape of ENV2 can be used to control VCO2 and/or the VCF. In ordinary use ENV1 will be used to control the VCA, and ENV2 will be used to control the VCF.
The Attack Knob determines the time taken to for the output voltage to rise from 0 to maximum. This ranges from 0 to 6600 Milliseconds (6.6 Seconds).
The Decay Knob dictates the amount of time required for the ENV1 output to fall from maximum to the sustain level set by the Sustain Knob, and from this sustain level back to 0 after the key is released.
The Sustain Knob is not a time constant but a voltage constant. This constant is the level at which the ENV1 output will be sustained for as long as a gate signal is present (i.e. as long as the key is held).
The Attack Knob determines the time taken to for the output voltage to rise from 0 to maximum. This ranges from 0 to 6000 Milliseconds (6 Seconds).
The Decay Knob selects the amount of time required for the ENV2 output to fall from maximum to the sustain level set by the Sustain Knob, and from this sustain level back to 0 after the key is released.
The Sustain Knob is not a time constant but a voltage constant. This constant is the level at which the ENV2 output will be sustained for as long as a gate signal is present (i.e. as long as the key is held).