1184 quad mixer vca (AKA 1183)

OK, it looks like @fredrik and you sorted it all out while I was sleeping. Good.

The 100k resistor could cause clipping for high level signals and high gains, but if you like it that way in this design, leave it like that, it can easily be replaced for those that don’t want the clipping.

If 10V peak-to-peak is to be the recommended “normal” signal level (which makes sense to allow for headroom etc), I’ll add that to the Kosmo Specification Wiki

Glad to see that we agree that the 2V Zener is not necessary on the signal input.
Given the voltage divider before the linear control voltage input, a 2V Zener diode is not necessary there either.

While analyzing the circuit to determine if a 2V protection Zener diode was necessary on the CV input, I noticed that the switch labeled “INV” doesn’t actually invert the effect of the control voltage as I expected it would, but it just adds an offset equivalent to about 5.6V on the CV input jack so it will just increase the output volume (and can be used with a negative going envelope to cause a drop in volume, but the envelope would need to have been inverted before being applied to this module’s CV input).

What is the expected voltage range out of an envelope generator?
Or said differently, what is the expected CV input range for this module for a normal envelope?
What does the #1157 Mini ADSR put out?
What do Eurorack envelope generator modules typically put out?

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