WC-81 Function Generator


Update - now includes Dark Mode! Just click on the DMT Audio logo on the top-right of the module to toggle between modes.

A fantastic emulation of the Buchla 281 Function Generator, this features 4 AD-style envelopes with control over attack and decay length from 1ms to 10 seconds. These envelopes can also be chained together to create more exciting, complex envelopes to liven up your sounds!



Input - Signal In - this can be a trigger or gate. The Attack phase is triggered by the rising edge of a signal greater than 2.5v.

Mode - 3 Modes of operation. From top to button on the 3-way switch:

  1. LFO Mode - once the Decay phase has ended, the Pulse Out will trigger and the function will restart with the Attack phase.
  2. Sustained Mode - If a Gate signal is passed to the input, once the Attack phase has ended, the output signal will stay high until the Gate signal goes LOW. This will then trigger the Decay phase.
  3. AD Mode - Once the Attack phase has ended, it will transition straight to the Decay phase - regardless of a Gate signal.
  4. Attack - Knob will control the Attack length of the signal, from 1ms up to 10 seconds. A CV signal connected to the Attack CV Input will modulate the Attack length dependent on the signal.

Decay - Knob will control the Decay length of the signal, from 1ms up to 10 seconds. A CV signal connected to the Decay CV Input will modulate the Decay length dependent on the signal.

Quadrature Mode (A-B, C-D) - When switched on, this will combine A&B, and C&D generators together in a 90-degree formation. This means that once function A's Decay phase has finished, function B's Attack phase will begin. Great for creating ADSR-style or more complicated envelopes.

Combination Attenuator - When using the Combo Out Jacks, this knob will determine the level of Function B or D in the mix.


Pulse Out - Once the Decay phase of a function has ended, this will output a short pulse signal. This can we used to chain functions together by connecting this to the Input Jack of the next function generator.

CV Out - Outputs the function signal.

Combo Out - Shared by A&B and C&D Generators - this a combination out, with the B/D mix determined by the attenuator knobs.

DMT Audio is not affiliated, associated, authorized, endorsed by, or in any way officially connected with Buchla.