WC-45 Sequential Voltage Source


Based on the Buchla 245/246, the WC-45 Voltage Source is a quad 5-step sequencer with an included Pulser which drives the sequencer, but can be used separately as well. Current Step, Pulse and Step Length are CV-addressable, and Stage Input switches allow you to change the sequence length, or even 'capture' the active step between two points - great for live improvisation! With individual trigger/gate inputs for each step, this module can also be used as a Preset Voltage selector for up to 4 outputs!


The Pulser generates a regular pulse signal which can be used on it's own or to control the sequencer.


Pulse Length - Essentially a Pulse Width control, this controls the percentage of time during the signal is HIGH versus LOW. This value is CV-controllable via the adjacent CV input jack.

Interval Time - The large knob controls the total length of time per step, and is CV-controllable via the above CV Input jack, which itself can be attenuverted using the knob adjacent to the input jack.

Stop - Stops the sequence - this can also be controlled electronically via a HIGH input signal into the CV Jack. Whilst stopped, pressing this button will also advance the sequencer along a step.

Start - Starts the sequence, this can also be controlled electronically via a HIGH input signal into the CV Jack.

Link - The Pulser and Sequencer sections of this module are essentially entirely separate, and the original hardware module required a jack between the PULSE and ADV jacks to control the sequencer. To save you the hassle, there's a LINK button in between, which replicates this functionality. If your sequencer isn't moving, try this button!


Ref - Similar to the REF outputs on the Behemoth, this will output a 0-5v negative ramp signal, the length of which is dependent on the Interval Time. Useful as a primitive envelope.

Pulse - Outputs a Pulse signal, controlled by the Pulse Length and Interval Time controls.



Adv. - Send a HIGH input signal to advance the step sequencer a step.

Step Voltage Controls - Control 4 independent rows of 5 steps each, from 0-5v.

Analog - A control voltage into this jack will determine the current step. For example, a 0-1v signal will change the step to Step 1, 1-2v to Step 2 and so on.

Stage Select Inputs - Sending a HIGH signal into any of these will automatically jump the sequencer to the associated step.

Sequence Boundary Switches - These interesting controls determine the start and end steps for the sequencer. However, there is a trick to them! The switches essentially 'constrain' the active step which can lead to some unpredictable sequences! See below example in the Tips & Tricks section.


Outs A-D - Outputs the control voltage for the relevant Sequence, based on the current step.

Gate Outs 1-5 - When the active step changes, a HIGH signal will be sent to the relevant Gate Out jack.

Tips and Tricks

As with the other modules in the West Coast Bundle - clicking the DMT Audio logo switch between dark and light mode.

Connect all four A-D outputs to a sequential switch to give you a 20-step sequence!

Connecting each CV Output to different Modulation Inputs, and controlling the steps manually gives you a basic Preset Selector!

The Sequence Boundary Switches work by constraining the active step. For example, if we set the switch between steps 2 and 3 to ON, if the current step is 1 or 2, then the sequence will go STEP 1, STEP 2, STEP 1, STEP 2 etc.. If the current step is 3, 4 or 5 when the switch is set, then the sequence will go STEP 3, STEP 4, STEP 5, STEP 3, STEP 4, STEP 5 etc.. Takes a bit of getting used to, but is great for live improvisation!

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