The tremolo action is therefore different than other types of tremolo and the amount of tremolo varies with a multitude of variables, most importantly the tremolo is “self-ducking” and decreases at higher signal amplitudes. Note particularly that bias tremolo is a somewhat crude tremolo circuit and it’s interaction with the power amp depends on many things including damping, bias, etc. On some amps high values of bias trem depth can result in excessive crossover distortion. On other amps the amount of tremolo can vary greatly between loud and soft playing. All this, however, is part of the allure of bias tremolo as it results in a particularly “organic” sound. Control of the bias tremolo is afforded by the Trem Freq and Trem Depth parameters. A modifier can be attached to Trem Depth to facilitate engaging and disengaging the tremolo via footswitch or for other applications.