When two audio sources are inputted, the output contains only the sum and difference frequencies of the two signals, while removing common frequencies. The audio result is useful for creating sounds with inharmonic frequency content, which is useful for synthesizing bell and metallic sounds. Cherry Audio's Rackmode Ring Modulator super accurately reproduces the rare Bode Frequency Shifter and includes a mod oscillator, featuring range controls, and multiple waveforms. Its pitch can also be "played" with a standard MIDI/USB keyboard.