Class FrequencyEnvelope

FrequencyEnvelope is an Envelope which ramps between baseFrequency and octaves. It can also have an optional exponent to adjust the curve which it ramps.

Example

const oscillator = new Tone.Oscillator().toDestination().start();
const freqEnv = new Tone.FrequencyEnvelope({
attack: 0.2,
baseFrequency: "C2",
octaves: 4
});
freqEnv.connect(oscillator.frequency);
freqEnv.triggerAttack();

Hierarchy (view full)

Constructors

Properties

attack: Unit.Time

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

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Min

0

Max

2

context: BaseContext

The context belonging to the node.

debug: boolean = false

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

decay: Unit.Time

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

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Min

0

Max

2

input: undefined | InputNode = undefined

Envelope has no input

name: string = "FrequencyEnvelope"

The name of the class

output: OutputNode = ...

The output signal of the envelope

release: Unit.Time

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

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Min

0

Max

5

sustain: number

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

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version: string = version

The version number semver

Accessors

  • get attackCurve(): EnvelopeCurve
  • The shape of the attack. Can be any of these strings:

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

    Can also be an array which describes the curve. Values in the array are evenly subdivided and linearly interpolated over the duration of the attack.

    Returns EnvelopeCurve

    Example

    return Tone.Offline(() => {
    const env = new Tone.Envelope(0.4).toDestination();
    env.attackCurve = "linear";
    env.triggerAttack();
    }, 1, 1);
  • set attackCurve(curve): void
  • Parameters

    Returns void

  • get blockTime(): number
  • The number of seconds of 1 processing block (128 samples)

    Returns number

    Example

    console.log(Tone.Destination.blockTime);
    
  • get 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.

    Returns number

  • set channelCount(channelCount): void
  • Parameters

    • channelCount: number

    Returns void

  • get 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.

    Returns ChannelCountMode

  • set channelCountMode(channelCountMode): void
  • Parameters

    • channelCountMode: ChannelCountMode

    Returns void

  • get 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".

    Returns ChannelInterpretation

  • set channelInterpretation(channelInterpretation): void
  • Parameters

    • channelInterpretation: ChannelInterpretation

    Returns void

  • get disposed(): 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.

    Returns boolean

  • get numberOfInputs(): number
  • The number of inputs feeding into the AudioNode. For source nodes, this will be 0.

    Returns number

    Example

    const node = new Tone.Gain();
    console.log(node.numberOfInputs);
  • get numberOfOutputs(): number
  • The number of outputs of the AudioNode.

    Returns number

    Example

    const node = new Tone.Gain();
    console.log(node.numberOfOutputs);
  • get releaseCurve(): EnvelopeCurve
  • The shape of the release. See the attack curve types.

    Returns EnvelopeCurve

    Example

    return Tone.Offline(() => {
    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);
    }, 1, 1);
  • set releaseCurve(curve): void
  • Parameters

    Returns void

  • get value(): number
  • Read the current value of the envelope. Useful for synchronizing visual output to the envelope.

    Returns number

Methods

  • 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.

    Parameters

    • length: number = 1024

    Returns Promise<Float32Array>

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

    Parameters

    Returns this

    Example

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

    Parameters

    Returns this

    Example

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

    Parameters

    Returns number

    Example

    const env = new Tone.Envelope(0.5, 1, 0.4, 2);
    env.triggerAttackRelease(2);
    setInterval(() => console.log(env.getValueAtTime(Tone.now())), 100);
  • Set multiple properties at once with an object.

    Parameters

    Returns this

    Example

    const filter = new Tone.Filter().toDestination();
    // set values using an object
    filter.set({
    frequency: "C6",
    type: "highpass"
    });
    const player = new Tone.Player("https://tonejs.github.io/audio/berklee/Analogsynth_octaves_highmid.mp3").connect(filter);
    player.autostart = true;
  • Convert the incoming time to seconds. This is calculated against the current TransportClass bpm

    Parameters

    Returns number

    Example

    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);
  • Convert the class to a string

    Returns string

    Example

    const osc = new Tone.Oscillator();
    console.log(osc.toString());
  • Trigger the attack/decay portion of the ADSR envelope.

    Parameters

    • Optional time: Unit.Time

      When the attack should start.

    • velocity: number = 1

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

    Returns this

    Example

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

    Parameters

    • duration: Unit.Time

      The duration of the sustain.

    • Optional time: Unit.Time

      When the attack should be triggered.

    • velocity: number = 1

      The velocity of the envelope.

    Returns this

    Example

    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);
  • Triggers the release of the envelope.

    Parameters

    • Optional time: Unit.Time

      When the release portion of the envelope should start.

    Returns this

    Example

    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");