files/en-us/web/api/audiobuffersourcenode/detune/index.md
{{APIRef("Web Audio API")}}
The detune property of the
{{domxref("AudioBufferSourceNode")}} interface is a k-rate {{domxref("AudioParam")}}
representing detuning of oscillation in cents.
For example, values of +100 and -100 detune the source up or down by one semitone, while +1200 and -1200 detune it up or down by one octave.
A k-rate {{domxref("AudioParam")}} whose value indicates the detuning of oscillation in cents.
[!NOTE] Though the
AudioParamreturned is read-only, the value it represents is not.
const audioCtx = new AudioContext();
const channelCount = 2;
const frameCount = audioCtx.sampleRate * 2.0; // 2 seconds
const myArrayBuffer = audioCtx.createBuffer(
channelCount,
frameCount,
audioCtx.sampleRate,
);
for (let channel = 0; channel < channelCount; channel++) {
const nowBuffering = myArrayBuffer.getChannelData(channel);
for (let i = 0; i < frameCount; i++) {
nowBuffering[i] = Math.random() * 2 - 1;
}
}
const source = audioCtx.createBufferSource();
source.buffer = myArrayBuffer;
source.connect(audioCtx.destination);
source.detune.value = 100; // value in cents
source.start();
{{Specifications}}
{{Compat}}