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.

AudioNode properties

Number of inputs	0
Number of outputs	1
Channel count	2
Channel count mode	max
Channel interpretation	speakers

Constructor

BaseAudioContext.createOscillator(options)

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);
}

OscillatorNode Playground

This is an interactive example demonstrating the OscillatorNode. You can adjust the parameters in real-time to hear and see how they affect the generated sound wave.

OscillatorNode interactive playground

Oscillator Node

Type

Sine

Type

Frequency: 440 Hz

440

Detune: 0 cents

0

Volume: 0.50

0.5

import { AudioContext } from 'react-native-audio-api';

const ctx = new AudioContext();
const oscillator = ctx.createOscillator();
const gain = ctx.createGain();

oscillator.type = 'sine';

oscillator.frequency.value = 440;
oscillator.detune.value = 0;
gain.gain.value = 0.50;

oscillator.connect(gain);
gain.connect(ctx.destination);
oscillator.start();

Properties

It inherits all properties from AudioScheduledSourceNode.

Name	Type	Default value	Description
detune Read only	AudioParam	0	a-rate AudioParam representing detuning of oscillation in cents.
frequency Read only	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

The above allows user to set any periodic wave.

Parameters	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)