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EZ Web Audio / DelayEffect

Class: DelayEffect

Defined in: packages/core/src/effects/delay-effect.ts:42

DelayEffect - Echo/delay effect with configurable time, feedback, and wet/dry mix.

Uses a DelayNode with a feedback loop to create repeating echoes. Feedback is clamped to [0, 0.99] to prevent infinite volume growth.

Extends BaseEffect for shared wet/dry mixing, bypass, and rampTo() functionality.

Example

typescript
import { createDelay, createSound } from 'ez-web-audio'

const sound = await createSound('guitar.mp3')
const delay = createDelay({ time: 0.3, feedback: 0.5, mix: 0.4 })
sound.addEffect(delay)
sound.play()

// Real-time control
delay.time = 0.5
delay.feedback = 0.7
delay.rampTo('time', 0.1, 2) // Smooth ramp over 2 seconds

Extends

Constructors

Constructor

new DelayEffect(audioContext, options): DelayEffect

Defined in: packages/core/src/effects/delay-effect.ts:52

Parameters

audioContext

AudioContext

options

DelayOptions = {}

Returns

DelayEffect

Overrides

BaseEffect.constructor

Accessors

bypass

Get Signature

get bypass(): boolean

Defined in: packages/core/src/effects/base-effect.ts:95

When true, signal bypasses the effect entirely (100% dry).

Returns

boolean

Set Signature

set bypass(v): void

Defined in: packages/core/src/effects/base-effect.ts:99

When true, effect is bypassed (passthrough)

Parameters
v

boolean

Returns

void

When true, effect is bypassed (passthrough)

Inherited from

BaseEffect.bypass


feedback

Get Signature

get feedback(): number

Defined in: packages/core/src/effects/delay-effect.ts:99

Feedback amount (0-0.99). Higher values = more repeats

Returns

number

Set Signature

set feedback(v): void

Defined in: packages/core/src/effects/delay-effect.ts:103

Parameters
v

number

Returns

void


input

Get Signature

get input(): AudioNode

Defined in: packages/core/src/effects/base-effect.ts:83

The input AudioNode (receives signal from chain)

Returns

AudioNode

The input AudioNode that receives signal from the chain

Inherited from

BaseEffect.input


maxTime

Get Signature

get maxTime(): number

Defined in: packages/core/src/effects/delay-effect.ts:109

Maximum delay time in seconds (read-only, set at construction)

Returns

number


mix

Get Signature

get mix(): number

Defined in: packages/core/src/effects/base-effect.ts:108

Wet/dry mix: 0 = fully dry (no effect), 1 = fully wet (all through effect). Uses equal-power crossfade for natural mixing.

Returns

number

Set Signature

set mix(v): void

Defined in: packages/core/src/effects/base-effect.ts:112

Wet/dry mix: 0 = fully dry (no effect), 1 = fully wet (full effect)

Parameters
v

number

Returns

void

Wet/dry mix: 0 = fully dry (no effect), 1 = fully wet (full effect)

Inherited from

BaseEffect.mix


output

Get Signature

get output(): AudioNode

Defined in: packages/core/src/effects/base-effect.ts:88

The output AudioNode (sends signal to next in chain)

Returns

AudioNode

The output AudioNode that sends signal to the next in chain

Inherited from

BaseEffect.output


time

Get Signature

get time(): number

Defined in: packages/core/src/effects/delay-effect.ts:88

Delay time in seconds

Returns

number

Set Signature

set time(v): void

Defined in: packages/core/src/effects/delay-effect.ts:92

Parameters
v

number

Returns

void

Methods

_clearListeners()

protected _clearListeners(): void

Defined in: packages/core/src/events/typed-event-emitter.ts:192

Remove every listener registered through this emitter (via addEventListener(), on(), or once()), regardless of how many or what event type they're bound to.

Native EventTarget has no removeAllListeners(). This works around that by aborting a shared AbortSignal threaded through every addEventListener() call this class makes, then swapping in a fresh AbortController so the instance can keep accepting new listeners afterward (e.g. if it's reused before being garbage collected).

Subclasses call this from their dispose() alongside neutering dispatchEvent — the neuter stops future emits, this stops stale listener closures from being retained/invoked at all.

Returns

void

Inherited from

BaseEffect._clearListeners


addEventListener()

Call Signature

addEventListener<K>(type, listener, options?): void

Defined in: packages/core/src/events/typed-event-emitter.ts:44

Add a typed event listener for known event types. Overloaded to provide type safety for known event types while remaining compatible with the native EventTarget API.

Type Parameters
K

K extends "dispose"

Parameters
type

K

The event type (key of TMap)

listener

(event) => void

Typed event handler

options?

Standard addEventListener options

boolean | AddEventListenerOptions

Returns

void

Inherited from

BaseEffect.addEventListener

Call Signature

addEventListener(type, listener, options?): void

Defined in: packages/core/src/events/typed-event-emitter.ts:49

Add a typed event listener for known event types. Overloaded to provide type safety for known event types while remaining compatible with the native EventTarget API.

Parameters
type

string

The event type (key of TMap)

listener

Typed event handler

EventListenerOrEventListenerObject | null

options?

Standard addEventListener options

boolean | AddEventListenerOptions

Returns

void

Inherited from

BaseEffect.addEventListener


dispose()

dispose(): void

Defined in: packages/core/src/effects/delay-effect.ts:113

Disconnect all internal audio nodes and emit a 'dispose' event.

Subclass disposal contract: Subclasses that create additional audio nodes (e.g., BiquadFilterNode, DynamicsCompressorNode, WaveShaperNode) MUST override dispose() to disconnect those nodes before calling super.dispose().

Returns

void

Example

typescript
public override dispose(): void {
  try { this.myNode.disconnect() } catch { /* already disconnected */ }
  super.dispose()
}

Idempotent — safe to call multiple times.

Overrides

BaseEffect.dispose


emit()

protected emit<K>(type, detail): void

Defined in: packages/core/src/events/typed-event-emitter.ts:95

Emit a typed event with the given detail.

Creates a CustomEvent with the provided detail and dispatches it on this target. Subclasses call this internally to fire lifecycle events.

Type Parameters

K

K extends "dispose"

Parameters

type

K

The event type to emit (key of TMap)

detail

BaseEffectEventMap[K]["detail"]

The event detail object (typed by TMap)

Returns

void

Inherited from

BaseEffect.emit


getAudioContext()

getAudioContext(): AudioContext

Defined in: packages/core/src/effects/base-effect.ts:121

Get the AudioContext used by this effect. Useful for external tools (e.g., LFO) that need the context.

Returns

AudioContext

Inherited from

BaseEffect.getAudioContext


getAudioParam()

protected getAudioParam(name): AudioParam | null

Defined in: packages/core/src/effects/delay-effect.ts:125

Map a parameter name to its underlying AudioParam. Subclasses implement this to expose their effect-specific parameters.

Parameters

name

string

The parameter name

Returns

AudioParam | null

The AudioParam, or null if not recognized

Overrides

BaseEffect.getAudioParam


getParam()

getParam(name): AudioParam | null

Defined in: packages/core/src/effects/base-effect.ts:134

Get a named AudioParam from this effect for external modulation.

Delegates to the subclass's getAudioParam() implementation. Returns null if the parameter name is not recognized.

Parameters

name

string

The parameter name (e.g., 'frequency', 'time', 'feedback')

Returns

AudioParam | null

The AudioParam, or null if not recognized

Inherited from

BaseEffect.getParam


getUnrampableParams()

protected getUnrampableParams(): readonly string[]

Defined in: packages/core/src/effects/base-effect.ts:243

Names of documented effect properties that are NOT backed by a single AudioParam (e.g. WaveShaper curve swaps, multi-node comb/allpass networks) and therefore cannot be smoothly ramped via rampTo(). rampTo() warns instead of silently no-op-ing when called with one of these names, so callers don't mistake "no-op" for "it worked."

Default: none. Subclasses override where applicable.

Returns

readonly string[]

Inherited from

BaseEffect.getUnrampableParams


off()

off<K>(type, listener): this

Defined in: packages/core/src/events/typed-event-emitter.ts:167

Unsubscribe from an event.

Note: Due to native EventTarget limitations, you must provide the same listener function reference that was used when subscribing.

Type Parameters

K

K extends "dispose"

Parameters

type

K

The event type to unsubscribe from

listener

(event) => void

The event handler function to remove

Returns

this

this for chaining

Example

typescript
const handler = (e) => console.log(e.detail)
emitter.on('play', handler)
// later...
emitter.off('play', handler)

Inherited from

BaseEffect.off


on()

on<K>(type, listener): this

Defined in: packages/core/src/events/typed-event-emitter.ts:116

Subscribe to one or more events. Supports chaining.

Type Parameters

K

K extends "dispose"

Parameters

type

The event type(s) to subscribe to (key or array of keys of TMap)

K | K[]

listener

(event) => void

The event handler function

Returns

this

this for chaining

Example

typescript
emitter.on('play', handlePlay).on('stop', handleStop)
emitter.on(['play', 'stop'], handleBoth)

Inherited from

BaseEffect.on


once()

once<K>(type, listener): this

Defined in: packages/core/src/events/typed-event-emitter.ts:141

Subscribe to an event once. Handler is removed after first invocation.

Type Parameters

K

K extends "dispose"

Parameters

type

K

The event type to subscribe to

listener

(event) => void

The event handler function

Returns

this

this for chaining

Example

typescript
emitter.once('end', () => console.log('Finished'))

Inherited from

BaseEffect.once


onParamRamped()

protected onParamRamped(param, value): number

Defined in: packages/core/src/effects/delay-effect.ts:138

ramp-setter-desync fix: rampTo('time'/'feedback', ...) routes through these same clamp functions the property setters use, and updates the shadow field, so the getter and the AudioParam can never diverge.

Parameters

param

string

value

number

Returns

number

Overrides

BaseEffect.onParamRamped


rampTo()

rampTo(param, value, duration): void

Defined in: packages/core/src/effects/base-effect.ts:164

Smoothly ramp a parameter to a target value over a duration.

Uses AudioParam.setTargetAtTime for glitch-free transitions. If the parameter name is not recognized, this is a no-op (a console.warn is emitted if the name is a real, documented effect property that just isn't backed by a single AudioParam — see getUnrampableParams).

Single write path: every ramped write is funneled through onParamRamped, the same hook subclasses use to keep their shadow getters honest. This guarantees effect.someParam reflects the ramp target immediately after calling rampTo(), and that the exact same validation/clamping a synchronous property-set would apply is also applied to ramped writes — the AudioParam and the getter can never diverge from each other.

Parameters

param

string

Parameter name (e.g., 'frequency', 'time', 'feedback')

value

number

Target value

duration

number

Ramp duration in seconds

Returns

void

Example

typescript
delay.rampTo('time', 0.5, 2)      // Ramp delay time to 0.5s over 2 seconds
filter.rampTo('frequency', 800, 1) // Ramp cutoff to 800Hz over 1 second

Inherited from

BaseEffect.rampTo


removeEventListener()

Call Signature

removeEventListener<K>(type, listener, options?): void

Defined in: packages/core/src/events/typed-event-emitter.ts:70

Remove a typed event listener for known event types. Overloaded to provide type safety for known event types while remaining compatible with the native EventTarget API.

Type Parameters
K

K extends "dispose"

Parameters
type

K

The event type (key of TMap)

listener

(event) => void

Typed event handler to remove

options?

Standard removeEventListener options

boolean | EventListenerOptions

Returns

void

Inherited from

BaseEffect.removeEventListener

Call Signature

removeEventListener(type, listener, options?): void

Defined in: packages/core/src/events/typed-event-emitter.ts:75

Remove a typed event listener for known event types. Overloaded to provide type safety for known event types while remaining compatible with the native EventTarget API.

Parameters
type

string

The event type (key of TMap)

listener

Typed event handler to remove

EventListenerOrEventListenerObject | null

options?

Standard removeEventListener options

boolean | EventListenerOptions

Returns

void

Inherited from

BaseEffect.removeEventListener