Sideband

A frequency component in a spectrum produced by a modulation of the original signal. In the case of amplitude and frequency modulation, sidebands occur in pairs on either side of the carrier frequency at a distance equal to the modulating frequency.

Amplitude modulation spectrum of two sine waves, carrier C and modulator M, showing the addition of a pair of sidebands, C + M and C - M, around the carrier.

Compare: Aural Harmonics, Band, Difference Tone, Modulated Carrier, Partial, Subharmonic, Summation Tone.

See Amplitude Modulation and Frequency Modulation for other diagrams and sound examples, and the FM Tutorial for sideband calculation.