Tremolo is an audio effect that produces periodic variation in the amplitude (volume) of a sound signal, creating a pulsating or quavering effect. The mechanism uses a low-frequency oscillator (LFO) to modulate the amplitude envelope of the audio signal: the LFO generates a periodic waveform — typically sine, triangle, or square — at a rate between 0.1 Hz and 20 Hz, and the instantaneous amplitude of the audio signal is multiplied by the LFO output (normalized to 0–1 range). Parameters include rate (LFO frequency in Hz, typically 0.1–10 Hz for musical tremolo), depth or intensity (how far amplitude swings from full volume to minimum, 0–100%), and waveform shape (sine for smooth pulsation, square for on/off gating effect). The persistence mechanism: analog tremolo circuits use an LFO driving a voltage-controlled amplifier in the audio path; digital tremolo implements amplitude multiplication in DSP code or as plugin effects (VST, AU, AAX); tremolo persists as a standard feature in guitar amplifiers, stompbox pedals, synthesizers, and studio software. [formal: tremolo | substrate: behavior | horizon: a moment | explicit: yes | epoch: 0.01]
Accepted ontology entry
tremolo
Tremolo is an audio effect that produces periodic variation in the amplitude (volume) of a sound signal, creating a pulsating or quavering effect. The mechanism uses a low-frequency oscillator (LFO) to modulate the amplitude envelope of th…
Definition
Why it is in scope
A human-made audio effect that periodically varies the amplitude of a sound signal to produce a pulsating or quavering sound, controlled by rate (LFO frequency) and depth — built to persist as a standard effect in guitar amplifiers, stompbox pedals, synthesizers, and studio processing.
Names and aliases
- tremoloen · CANONICAL
Relations from this entry
- amplitude-modulationDEPENDS_ON →
Tremolo modulates signal amplitude using a low-frequency oscillator (LFO). Remove amplitude-modulation as a mechanism — no way to vary amplitude in a periodic fashion — and tremolo cannot operate. This passes the Law 8 removal test. Pin sense: amplitude-modulation as the mechanism of varying signal level by a modulating waveform.
- audio-effectINSTANCE_OF →
tremolo is a specific audio effect that produces a regular oscillation of volume (amplitude) at a low frequency. A competent speaker calls tremolo an audio effect.
- lfoDEPENDS_ON →
Tremolo cannot operate without an LFO: its defining mechanism IS an LFO generating a periodic waveform that modulates amplitude. Remove the LFO — the periodic amplitude variation that constitutes tremolo disappears. The LFO is the signal source that tremolo depends on for its core operation, not merely a tool it optionally uses.
- amplitude-modulationINSTANCE_OF →
Tremolo is a specific kind of amplitude modulation: it varies the amplitude of a carrier (audio) signal using a modulating signal (LFO waveform), producing the characteristic pulsating effect. Competent speaker test: 'tremolo is a form of amplitude modulation' — yes. Nearest kind is amplitude-modulation, which is already an accepted entry with its own accepted definition.
Relations to this entry
No accepted relations in this direction.
Record identity
- Created
- Sep 6, 2026, 6:52 PM UTC
- Content hash
- 1140bb1641400366117501c49cb4f4c2bd351fea8ede49874ead8f013a1ae91b