This command adds flanger to each selected Sound by mixing the original signal with a delayed copy modulated by a periodic function (sinusoidal or triangular), creating a swept comb filter effect.
This implementation includes a feedback loop for metallic resonance, an optional high-pass filter to preserve low-end clarity, and a 180° stereo phase offset for enhanced spatial width.
The resulting new Sound(s) will appear selected in the list of objects.
Adapted from the procedures described at: https://www.dsprelated.com/freebooks/pasp/Flanging.html and https://wiki.analog.com/resources/tools-software/sigmastudio/toolbox/adialgorithms/flanger