GR-331

Dual Envelator

Courtesy/Thanks to: Wiard

Description:

The Wiard envelope generator, the Envelator , is a multifunction dual slope linear function generator. The module contains two identical units.

The attack and decay slopes are individually voltage controllable with input attenuators. Each unit outputs the envelope, inverse of the envelope (negative going envelope), a voltage step signal during the attack phase, and a pulse at the end of the decay phase. The gate input has a three position switch which selects: Attack-Release where the output remains high as long as the gate is high, Attack-Decay where the decay phase begins immediately after the attack phase regardless of the gate level at the gate input. Cycle where the gate input is connected to the end pulse which causes the unit to act as an low frequency oscillator (LFO). The LFO extends into the low audio range and has triangle and square outputs. Any triangular or sawtooth shape or pulse width can be adjusted by the attack and decay controls.

The module also contains a DC coupled voltage controlled cross-fader which forms the sustain control when patched as a classic ADSR. It can also be used to mix two modulation sources when patched as two LFOs. The cross-fader will also handle audio signal through the full audio range. This is useful for replicating oscillator waveshapers which cross-fade from a sine wave signal to a waveform with higher harmonic content. An example would be the Buchla Model 258 oscillator.


The Envelator module contains:

• Two Multi-mode envelope generators/oscillators which will work in the low audio range
• A voltage "cross-fader" which will work both for control voltages and audio signals