oscillator-node.mdx

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import AudioNodePropsTable from "@site/src/components/AudioNodePropsTable" import { Optional, ReadOnly } from '@site/src/components/Badges';

import InteractivePlayground from '@site/src/components/InteractivePlayground'; import { useOscillatorPlayground } from '@site/src/components/InteractivePlayground/OscillatorExample/useOscilatorPlayground';

OscillatorNode

The OscillatorNode is an AudioScheduledSourceNode which represents a simple periodic wave signal. Similar to all of AudioScheduledSourceNodes, it can be started only once. If you want to play the same sound again you have to create a new one.

Constructor

constructor(context: BaseAudioContext, options?: OscillatorOptions)

OscillatorOptions

Inherits all properties from AudioNodeOptions

Parameter	Type	Default
type	OscillatorType	sine	Initial value for type.
frequency	number	440	Initial value for frequency.
detune	number	0	Initial value for detune.

Or by using BaseAudioContext factory method: BaseAudioContext.createOscillator()

Example

import React, { useRef } from 'react';
import {
  AudioContext,
  OscillatorNode,
} from 'react-native-audio-api';

function App() {
  const audioContextRef = useRef<AudioContext | null>(null);
  if (!audioContextRef.current) {
    audioContextRef.current = new AudioContext();
  }
  const oscillator = audioContextRef.current.createOscillator();
  oscillator.connect(audioContextRef.current.destination);
  oscillator.start(audioContextRef.current.currentTime);
}

Properties

It inherits all properties from AudioScheduledSourceNode.

Name	Type	Default value	Description
detune	AudioParam	0	a-rate AudioParam representing detuning of oscillation in cents.
frequency	AudioParam	440	a-rate AudioParam representing frequency of wave in herzs.
type	OscillatorType	sine	String value represening type of wave.

Methods

It inherits all methods from AudioScheduledSourceNode.

setPeriodicWave

Sets any periodic wave.

Parameter	Type	Description
wave	PeriodicWave	Data representing custom wave. See for reference

Returns undefined.

Remarks

detune

• Nominal range is: -∞ to ∞.
• For example value of 100 detune the source up by one semitone, whereas -1200 down by one octave.

frequency

• 440 Hz is equivalent to piano note A4.
• Nominal range is: $-\frac{\text{sampleRate}}{2}$ to $\frac{\text{sampleRate}}{2}$ (sampleRate value is taken from AudioContext)