A utility module that provides "zero-crossing" processing for Gate and CV signals, taking inspiration from Expert Sleepers Persephone and a request by a user for this feature some of my Envelope/VCA modules. This process is designed to remove or reduce clicks generated when gates/CVs allow a signal through when the signal is not at zero (and especially when it is it at +5V or -5V).
The module has two independent sections, one for processing Gate signals and the second for processing CV signals. As the zero-crossing process is aligned at sample level, each input has a thru output as well as a processed output so that the source can be used in modules further down the signal chain knowing that they are fully aligned at the internal sample rate. Each section has a signal path which is needed to provide the zero-crossing information, but which also offers a VCA out with the processed Gate or CV.
The Gate Processing section adjusts the start and end time of the gate signal so that they are always at the time that the input signal crosses zero. This can be controlled so that it senses zero-crossing in any direction, or just crossing up or down. This section also allows the minimum (or gate on time) to be aligned to multiple crossings to work better with complex waveforms. Note that the Gate Processing section does not remove all clicks at higher audio frequencies due to the limitations of the internal sample rate meaning that a waveform may be crossing zero by a significant amount.
The CV Processing section uses a sample and hold model on the CV, so that the CV is stepped whenever the signal crosses zero, so that e.g. aggressive envelopes can be tamed so that they don't cause clicks. This can be controlled so that it senses zero-crossing in any direction, or just crossing up or down. This section also allows the minimum (or gate on time) to be aligned to multiple crossings to work better with complex waveforms.
Also included in Andrew Macaulay's Gate and Trigger Collection, Andrew Macaulay's Envelope and LFO Collection and Andrew Macaulay's Ultimate Bundle.