Three cascaded wavefolding sections.
Control knobs manage input attenuation for each input.
When no input is present at "Offset", the Offset knob adds +/-5V to the mixed input.
When no input is present at "Feedback", the Feedback knob will add a limited amount of feedback from stage 3 back into the module.
Each stage is available as an output. Stage 2 is phase inverted.
A common wavefolder circuit will subtract a signal from a clipped version of that signal. The kind of clipping implemented will determine the behavior of the wavefolder.
For this module a JFET based sine shaping circuit was used, originally described by Middlebrook and Richer. This is very soft clipping behavior, and gives the resulting tone more roundness.
Cascading folding sections results in more folds as the input level is increased. More complex folding behavior can be achieved by adding gain to each stage. This way the folds from the first stage will propagate exponentially, resulting in behavior using 3 stages that would require 9 if no gain was added.
In total, the module applies ~50dB gain at the 3rd stage output. With Offset and Feedback, this module can easily hit the power rails on output. Attenuation is encouraged before sending to a mixer or other non-Gauche module, which are designed with this behavior in mind.
Voltage control was elided on this module for ease of production as well as a strong focus on manual control. Using a VCA before any of the inputs will provide classic wavefolder voltage control.
As of Jun 08, 2025 this module is not available for order through this website. The initial batch of 16 was ordered before tariffs on international orders were imposed. A closed beta of the initial batch is underway, while new options are explored for PCB manufacturing.
A future revision of this module is planned, after the beta period is over.
