SYNTHESIS · EXPLORE SOUND
LFO and
modulation.
A slow oscillator that sets sound in motion: choose what it modulates, how fast it moves and its waveform, then listen to the result.
Stopped
The sound
Carrier waveform
What does the LFO modulate?
The movement
LFO waveform
LFO waveform
4 Hz · depth 60 %Modulated signal
Amplitude (tremolo)A calculated illustration, not a measurement of the audio signal.
The scale stays fixed when you change frequencies. Show more time to see a slow LFO, or less time to see individual carrier cycles.
WHAT IS HAPPENING
One movement.
Three ways to hear it.
Amplitude → tremolo. The LFO raises and lowers the volume. At 100% depth, gain ranges from zero to one. At zero depth, the volume stays constant.
Frequency → vibrato. The pitch moves around the carrier frequency. Here, the maximum deviation is ±50% of that frequency: symmetrical in hertz, not in semitones.
Filter → wah. The LFO moves the cutoff of a low-pass filter. Try a sawtooth or square wave to hear how its harmonics change. At zero depth, the filter still works, but its cutoff stays fixed.
Rate. The LFO frequency sets the number of cycles per second: 0.5 Hz takes two seconds per cycle; 4 Hz completes four cycles per second.
Waveform. A sine wave changes smoothly, a triangle follows straight slopes, a square switches between two values, and a sawtooth combines a ramp with a jump.
Try and compare. Start at 1 Hz, switch targets, then increase the depth. The LFO acts as a control signal: it is not connected directly to the speakers.