This is a simple ring-mod effect with a timbre control.
This effect works like a tremolo but multiplying the signal with a full range (bipolar) modulator rather than half.
It has a basic anti-aliasing filter (2x) and a timbre control for the modulating signal.
- Frequency of the sine modulator signal generated internally.
- Modulation depth. From 0% to 50% will produce amplitude modulation, 50% to 100% ring modulation.
- Difference in modulator phase applied between left and right channels.
- How much extra harmonic content is added to the modulator.
For an "analog" flavor of ring-mod, adjust the depth to about 80%. By lowering the depth, part of the original signal is allowed to leak through as occurs in some electronic ring-mod effects. Adjust the timbre to about 10% to add some extra harmonic content which would be present due to imperfect sine waveform generators.
At 50% the effect becomes AM which means the original carrier signal will come through at full amplitude. Carrier + sum + difference.
At 100% the effect is a ring-mod which means the original carrier frequency is no longer audible. Sum + difference only.