Modulation Wheel

A synthesizer’s modulation wheel, also known as a mod wheel, is a control that enables the user to alter the amount of modulation being applied to the sound being produced by the synthesizer. Modulation, which can produce various effects such as vibrato, tremolo, and pitch bend, is the process of using one signal to control or affect another signal. The modulation wheel can make expressive changes to the sound in real-time and is typically situated to the keyboard’s left. The same effect can be produced on some synthesizers using a modulation lever or button. Depending on the synth, the modulation source and destination can change. An LFO modulating the pitch or the filter cutoff is one example.