Part 11

Amplitude Modulation

Multiplying signals creates new frequencies. Sidebands appear at the sum and difference of carrier and modulator. At low modulator rates you hear tremolo; push the modulator into audio range and the result is metallic, bell-like tones. Switch to ring modulation (bipolar multiply) and the carrier vanishes, leaving only the alien sidebands.

Read the original article on Sound On Sound →
Mod
110 Hz
AM
Carrier
440 Hz
VCA
Gain
Output
Preset
Sidebands: 330 Hz (C - M)   440 Hz (C)   550 Hz (C + M)
Carrier
Modulator
Waveform
Spectrum (Hz)