Envelope

Envelope is an ADSR envelope generator. Envelope outputs a signal which can be connected to an AudioParam or Tone.Signal.

/\ / \ / \ / \ / \___________ / \ / \ / \ / \

const env = new Tone.Envelope({
	attack: 0.1,
	decay: 0.2,
	sustain: 0.5,
	release: 0.8,
}).toDestination();
env.triggerAttackRelease(0.5);

Constructor

new Envelope (
attack?:Time ,

The amount of time it takes for the envelope to go from0 to it's maximum value.

decay?:Time ,

The period of time after the attack that it takes for the envelopeto fall to the sustain value. Value must be greater than 0.

sustain?:NormalRange ,

The percent of the maximum value that the envelope rests at untilthe release is triggered.

release?:Time

The amount of time after the release is triggered it takes to reach 0.Value must be greater than 0.

) => Envelope
new Envelope (
options?:Partial<EnvelopeOptions >
) => Envelope

Properties

attack #

Time

When triggerAttack is called, the attack time is the amount of time it takes for the envelope to reach it's maximum value.

/\ /X \ /XX \ /XXX \ /XXXX \___________ /XXXXX \ /XXXXXX \ /XXXXXXX \ /XXXXXXXX \
Range: 0 to 2

attackCurve #

EnvelopeCurve

The shape of the attack. Can be any of these strings:

  • "linear"
  • "exponential"
  • "sine"
  • "cosine"
  • "bounce"
  • "ripple"
  • "step"

const env = new Tone.Envelope(0.4).toDestination();
env.attackCurve = "linear";
env.triggerAttack();

blockTime #

readonly Seconds

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


console.log(Tone.Destination.blockTime);

channelCount #

number

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

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

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 #

BaseContext

The context belonging to the node.

debug #

boolean

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

decay #

Time

After the attack portion of the envelope, the value will fall over the duration of the decay time to it's sustain value.

/\ / X\ / XX\ / XXX\ / XXXX\___________ / XXXXX \ / XXXXX \ / XXXXX \ / XXXXX \
Range: 0 to 2

decayCurve #

BasicEnvelopeCurve

The shape of the decay either "linear" or "exponential"


const env = new Tone.Envelope({
	sustain: 0.1,
	decay: 0.5
}).toDestination();
env.decayCurve = "linear";
env.triggerAttack();

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.

input #

InputNode | undefined

Envelope has no input

numberOfInputs #

readonly number

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


const node = new Tone.Gain();
console.log(node.numberOfInputs);

numberOfOutputs #

readonly number

The number of outputs of the AudioNode.


const node = new Tone.Gain();
console.log(node.numberOfOutputs);

output #

OutputNode

The output signal of the envelope

release #

Time

After triggerRelease is called, the envelope's value will fall to it's miminum value over the duration of the release time.

/\ / \ / \ / \ / \___________ / X\ / XX\ / XXX\ / XXXX\
Range: 0 to 5

releaseCurve #

EnvelopeCurve

The shape of the release. See the attack curve types.


const env = new Tone.Envelope({
	release: 0.8
}).toDestination();
env.triggerAttack();
// release curve could also be defined by an array
env.releaseCurve = [1, 0.3, 0.4, 0.2, 0.7, 0];
env.triggerRelease(0.2);

sampleTime #

readonly Seconds

The duration in seconds of one sample.


console.log(Tone.Transport.sampleTime);

sustain #

NormalRange

The sustain value is the value which the envelope rests at after triggerAttack is called, but before triggerRelease is invoked.

/\ / \ / \ / \ / \___________ / XXXXXXXXXXX\ / XXXXXXXXXXX \ / XXXXXXXXXXX \ / XXXXXXXXXXX \

value #

readonly NormalRange

Read the current value of the envelope. Useful for synchronizing visual output to the envelope.

static version #

string

The version number semver

Methods

asArray #

Render the envelope curve to an array of the given length. Good for visualizing the envelope curve. Rescales the duration of the envelope to fit the length.

asArray (
length= 1024:number
) => Promise<Float32Array >

cancel #

Cancels all scheduled envelope changes after the given time.

cancel (
after?:Time
) => this

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 envelope to a destination node.

connect (
destination:InputNode ,
outputNumber= 0:number ,
inputNumber= 0: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();
console.log(osc.get());
get ( ) => EnvelopeOptions

static getDefaults #

Returns all of the default options belonging to the class.

getDefaults ( ) => EnvelopeOptions

getValueAtTime #

Get the scheduled value at the given time. This will return the unconverted (raw) value.


const env = new Tone.Envelope(0.5, 1, 0.4, 2);
env.triggerAttackRelease(2);
setInterval(() => console.log(env.getValueAtTime), 100);
getValueAtTime (
time:Time
) => NormalRange

immediate #

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


setInterval(() => {
	console.log(Tone.immediate());
}, 100);
immediate ( ) => Seconds

now #

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


setInterval(() => {
	console.log(Tone.now());
}, 100);
now ( ) => Seconds

set #

Set multiple properties at once with an object.


const filter = new Tone.Filter();
// set values using an object
filter.set({
	frequency: 300,
	type: "highpass"
});
set ( ) => this

toDestination #

Connect the output to the context's destination node.


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

toFrequency #

Convert the input to a frequency number


const gain = new Tone.Gain();
console.log(gain.toFrequency("4n"));
toFrequency (
freq:Frequency
) => Hertz

toMaster # DEPRECATED

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

toMaster ( ) => this

toSeconds #

Convert the incoming time to seconds


const gain = new Tone.Gain();
console.log(gain.toSeconds("4n"));
toSeconds (
time?:Time
) => Seconds

toString #

Convert the class to a string


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

toTicks #

Convert the input time into ticks


const gain = new Tone.Gain();
console.log(gain.toTicks("4n"));
toTicks (
time?:Time | TimeClass
) => Ticks

triggerAttack #

Trigger the attack/decay portion of the ADSR envelope.


const env = new Tone.AmplitudeEnvelope().toDestination();
const osc = new Tone.Oscillator().connect(env).start();
// trigger the attack 0.5 seconds from now with a velocity of 0.2
env.triggerAttack("+0.5", 0.2);
triggerAttack (
time?:Time ,

When the attack should start.

velocity= 1:NormalRange

The velocity of the envelope scales the vales.number between 0-1

) => this

triggerAttackRelease #

triggerAttackRelease is shorthand for triggerAttack, then waiting some duration, then triggerRelease.


const env = new Tone.AmplitudeEnvelope().toDestination();
const osc = new Tone.Oscillator().connect(env).start();
// trigger the release 0.5 seconds after the attack
env.triggerAttackRelease(0.5);
triggerAttackRelease (
duration:Time ,

The duration of the sustain.

time?:Time ,

When the attack should be triggered.

velocity= 1:NormalRange

The velocity of the envelope.

) => this

triggerRelease #

Triggers the release of the envelope.


const env = new Tone.AmplitudeEnvelope().toDestination();
const osc = new Tone.Oscillator({
	type: "sawtooth"
}).connect(env).start();
env.triggerAttack();
// trigger the release half a second after the attack
env.triggerRelease("+0.5");
triggerRelease (
time?:Time

When the release portion of the envelope should start.

) => this