LFO stands for low frequency oscillator. LFO produces an output signal which can be attached to an AudioParam or Tone.Signal in order to modulate that parameter with an oscillator. The LFO can also be synced to the transport to start/stop and change when the tempo changes.

return Tone.Offline(() => {
	const lfo = new Tone.LFO("4n", 400, 4000).start().toDestination();
}, 0.5, 1);



new LFO (
frequency?:Frequency ,

The frequency of the oscillation.Typically, LFOs will be in the frequency range of 0.1 to 10 hertz.

min?:undefined | number ,

The minimum output value of the LFO.

max?:undefined | number

The maximum value of the LFO.

) => LFO
new LFO (
options?:Partial<LFOOptions >
) => LFO


amplitude #

Param<"normalRange" >

The amplitude of the LFO, which controls the output range between the min and max output. For example if the min is -10 and the max is 10, setting the amplitude to 0.5 would make the LFO modulate between -5 and 5.

blockTime #

readonly Seconds

The number of seconds of 1 processing block (128 samples)


channelCount #


channelCount is the number of channels used when up-mixing and down-mixing connections to any inputs to the node. The default value is 2 except for specific nodes where its value is specially determined.

channelCountMode #


channelCountMode determines how channels will be counted when up-mixing and down-mixing connections to any inputs to the node. The default value is "max". This attribute has no effect for nodes with no inputs.

  • "max" - computedNumberOfChannels is the maximum of the number of channels of all connections to an input. In this mode channelCount is ignored.
  • "clamped-max" - computedNumberOfChannels is determined as for "max" and then clamped to a maximum value of the given channelCount.
  • "explicit" - computedNumberOfChannels is the exact value as specified by the channelCount.

channelInterpretation #


channelInterpretation determines how individual channels will be treated when up-mixing and down-mixing connections to any inputs to the node. The default value is "speakers".

context #


The context belonging to the node.

convert #


If the input value is converted using the units

debug #


Set this debug flag to log all events that happen in this class.

disposed #

readonly boolean

Indicates if the instance was disposed. 'Disposing' an instance means that all of the Web Audio nodes that were created for the instance are disconnected and freed for garbage collection.

frequency #

Signal<"frequency" >

The frequency value of the LFO

input #


There is no input node

max #


The maximum output of the LFO.

min #


The minimum output of the LFO.

numberOfInputs #

readonly number

The number of inputs feeding into the AudioNode. For source nodes, this will be 0.

const node = new Tone.Gain();

numberOfOutputs #

readonly number

The number of outputs of the AudioNode.

const node = new Tone.Gain();

output #


The output of the LFO

partials #

number []

The oscillator's partials array: See Oscillator.partials

phase #


The phase of the LFO.

sampleTime #

readonly Seconds

The duration in seconds of one sample.


state #

readonly BasicPlaybackState

Returns the playback state of the source, either "started" or "stopped".

type #


The type of the oscillator: See Oscillator.type

units #


The output units of the LFO.

static version #


The version number semver


chain #

Connect the output of this node to the rest of the nodes in series.

const player = new Tone.Player("https://tonejs.github.io/audio/drum-samples/handdrum-loop.mp3");
player.autostart = true;
const filter = new Tone.AutoFilter(4).start();
const distortion = new Tone.Distortion(0.5);
// connect the player to the filter, distortion and then to the master output
player.chain(filter, distortion, Tone.Destination);
chain (
...nodes:InputNode []
) => this

connect #

connect the output of a ToneAudioNode to an AudioParam, AudioNode, or ToneAudioNode

connect (
node:InputNode ,

the destination to connect to

outputNum?:undefined | number ,

the optional output number

inputNum?:undefined | number

the input number

) => this

disconnect #

disconnect the output

disconnect (
destination?:InputNode ,
outputNum= 0:number ,
inputNum= 0:number
) => this

dispose #

Dispose and disconnect

dispose ( ) => this

fan #

connect the output of this node to the rest of the nodes in parallel.

const player = new Tone.Player("https://tonejs.github.io/audio/drum-samples/conga-rhythm.mp3");
player.autostart = true;
const pitchShift = new Tone.PitchShift(4).toDestination();
const filter = new Tone.Filter("G5").toDestination();
// connect a node to the pitch shift and filter in parallel
player.fan(pitchShift, filter);
fan (
...nodes:InputNode []
) => this

get #

Get the object's attributes.

const osc = new Tone.Oscillator();
get ( ) => LFOOptions

static getDefaults #

Returns all of the default options belonging to the class.

getDefaults ( ) => LFOOptions

immediate #

Return the current time of the Context clock without any lookAhead.

setInterval(() => {
}, 100);
immediate ( ) => Seconds

now #

Return the current time of the Context clock plus the lookAhead.

setInterval(() => {
}, 100);
now ( ) => Seconds

set #

Set multiple properties at once with an object.

const filter = new Tone.Filter().toDestination();
// set values using an object
	frequency: "C6",
	type: "highpass"
const player = new Tone.Player("https://tonejs.github.io/audio/berklee/Analogsynth_octaves_highmid.mp3").connect(filter);
player.autostart = true;
set ( ) => this

start #

Start the LFO.

start (

The time the LFO will start

) => this

stop #

Stop the LFO.

stop (

The time the LFO will stop

) => this

sync #

Sync the start/stop/pause to the transport and the frequency to the bpm of the transport

const lfo = new Tone.LFO("8n");
// the rate of the LFO will always be an eighth note, even as the tempo changes
sync ( ) => this

toDestination #

Connect the output to the context's destination node.

const osc = new Tone.Oscillator("C2").start();
toDestination ( ) => this

toFrequency #

Convert the input to a frequency number

const gain = new Tone.Gain();
toFrequency (
) => Hertz


Connect the output to the context's destination node. See toDestination

toMaster ( ) => this

toSeconds #

Convert the incoming time to seconds. This is calculated against the current Tone.Transport bpm

const gain = new Tone.Gain();
setInterval(() => console.log(gain.toSeconds("4n")), 100);
// ramp the tempo to 60 bpm over 30 seconds
Tone.getTransport().bpm.rampTo(60, 30);
toSeconds (
) => Seconds

toString #

Convert the class to a string

const osc = new Tone.Oscillator();
toString ( ) => string

toTicks #

Convert the input time into ticks

const gain = new Tone.Gain();
toTicks (
time?:Time | TimeClass
) => Ticks

unsync #

unsync the LFO from transport control

unsync ( ) => this