The Tortenmann TT-3 Tremolo is a musical instrument effects unit that produces a classic tremolo effect, i.e. an amplitude modulation controlled by a sinusoidal low frequency wave. Speed and depth of the modulation, as well as the output level are continiously adjustable. The shape of the modulation waveform is sensitive to the depth setting, resulting in an effect that changes over from a soft tremolo at low depth settings to a hard, chopper-like effect at high settings. The effect can be turned off and the unit be used as a full range booster.