Currently there is no documentation for the VCV FADE module. The following is unofficial documentation based on my observation of how the module behaves.
VCV Fundamental FADE
FADE has a pair of signal inputs (IN 1, IN 2), and signal outputs (OUT 1, OUT 2).
The X FADE knob controls what percentage of each input signal is directed to the opposite output, with the remainder going to its own output. The response is linear. The module works equally well with audio or CV inputs.
| X FADE | OUT 1 | OUT 2 |
|---|---|---|
| 0% | IN 1 100% IN 2 0% |
IN 1 0% IN 2 100% |
| 25% | IN 1 75% IN 2 25% |
IN 1 25% IN 2 75% |
| 50% | IN 1 50% IN 2 50% |
IN 1 50% IN 2 50% |
| 75% | IN 1 25% IN 2 75% |
IN 1 75% IN 2 25% |
| 100% | IN 1 0% IN 2 100% |
IN 1 100% IN 2 0% |
The X FADE CV input offsets the value of the X FADE knob, and accepts bipolar input. The cross fade CV may be inverted and or attenuated by the X FADE CV attenuverter knob. Each volt of CV equates to 10% offset applied to the crossfade value.
Effective crossfade % = Knob % + (CV input * Attenuverter % * 10%) The final effective crossfade % is constrained to between 0% and 100%
So if the X FADE knob is at 50%, and the X FADE CV input is 5V, and the CV attenuverter is -50%, then the effective crossfade is 50% + (5*(-50/100) * 10%) = 50% + (-2.5 * 10%) = 25%
FADE is fully polyphonic. The number of channels output to OUT 1 and OUT 2 is equal to the maximum number of channels found across IN 1 and IN 2. Any mono input on IN 1, IN 2, or X FADE CV is replicated to match the number of output channels. But if an input is polyphonic, then any missing channels are treated as constant 0V.
Note that excess channels at the X FADE CV input are ignored. In other words, the CV input never determines the number of output channels.
If FADE is bypassed, then IN 1 is passed unaltered to OUT 1, and IN 2 to OUT 2.
Patch Tips
One possible use for FADE is to convert a mono signal into stereo with panning. The mono signal would be patched to IN 1, and OUT 1 would be the left output, and OUT 2 the right output. If the X FADE is fully counterclockwise at 0%, then the output is panned hard left. If at midpoint, then the output is center (50% equally to left and right). At fully clockwise at 100%, then the output is panned hard right. Patch an LFO to the CV input to dynamically pan the signal.
Another possible use is as a gate controlled switch: 2->1, or 1->2.
Set the X FADE knob to 0 (fully counterclockwise), and patch controlling CV to the CV input. To select one input out of two to be sent to a target, patch the two different inputs to IN 1 and IN 2, and patch OUT 1 to your destination. A low (0V) CV signal will sent IN 1 to your target. A high gate (10V) will send IN 2 to your target.
To send one input to one of two destinations, patch the input signal to IN 1, and patch OUT 1 to one target, and OUT 2 to the other. A low CV signal will send the input to OUT 1, and a high gate will send the input to OUT 2.