Tremulant

The Tremulant is an overdrive tremolo pedal.
IIt has a heavy-duty true-bypass footswitch and four controls that manipulate the rate.

The depth, the drive and and the level of the signal.

It is designed for sine wave tremolo effect tones with symmetrical modulation and frequency range(rate) from 1Hz to 13Hz.
With the Depth knob you can adjust the modulation level from 0% to 100% if you want more “choppy” effect.

The drive stage is after the modulation circuit and it’s adjustable. The more gain you give the more the peaks of the modulated signal gets distorted. Watch the video here with the full review that Premier Guitar Magazine has done for better understaning.