5x wavefolder – Erica Synths EDU DIY Wavefolder Eurorack Module Kit User Manual
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2.5x WAVEFOLDER
Now, a double wavefolder is nice, but I’d still like to add a bit more zing. For that, we just
have to increase the gain of the first folding stage’s output bu
ff
er.
Because if it’s more
than 1, the signal will get folded one additional time for free
.
Why is that? Because coming into the second stage, the signal will now wiggle across the
thresholds one additional time. In my experiments, increasing the gain by a factor of
around 2 gave me the best results. So we’ll replace the 10k feedback resistor with a 22k.
Now, to keep our intensity knob’s behavior the same, we’ll have to adjust the attenuator’s
range. Because otherwise, the second stage will fold the signal even at minimum
intensity. To avoid that, we’ll halve the baseline resistance in the attenuator.
That way, at
minimum intensity, the signal is occupying only half the area inside the first stage’s
folding thresholds
. Blow that up by a factor of 2, and the result should fit snugly
between the second stage’s folding thresholds again.
As a final touch, we’ll get the circuit’s output volume up to the standard 10 V peak-to-
peak. For that, we just have to bump the second output bu
ff
er’s gain to 20 by increasing
its feedback resistance to 200k.
You can try this chapter’s circuit in a simulator. I’ve already set it up for you right here:
you can change all values by double clicking on components.
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