BaseAudioContext: createDynamicsCompressor() method
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2021.
The createDynamicsCompressor() method of the BaseAudioContext Interface is used to create a DynamicsCompressorNode, which can be used to apply compression to an audio signal.
Compression lowers the volume of the loudest parts of the signal and raises the volume of the softest parts. Overall, a louder, richer, and fuller sound can be achieved. It is especially important in games and musical applications where large numbers of individual sounds are played simultaneously, where you want to control the overall signal level and help avoid clipping (distorting) of the audio output.
Note:
The DynamicsCompressorNode()
constructor is the recommended way to create a DynamicsCompressorNode; see
Creating an AudioNode.
Syntax
createDynamicsCompressor()
Parameters
None.
Return value
Examples
The code below shows how to use createDynamicsCompressor()
to add compression to an audio track. For a more complete example, have a look at our basic Compressor example (view the source code).
// Create a MediaElementAudioSourceNode
// Feed the HTMLMediaElement into it
const source = audioCtx.createMediaElementSource(myAudio);
// Create a compressor node
const compressor = audioCtx.createDynamicsCompressor();
compressor.threshold.setValueAtTime(-50, audioCtx.currentTime);
compressor.knee.setValueAtTime(40, audioCtx.currentTime);
compressor.ratio.setValueAtTime(12, audioCtx.currentTime);
compressor.attack.setValueAtTime(0, audioCtx.currentTime);
compressor.release.setValueAtTime(0.25, audioCtx.currentTime);
// connect the AudioBufferSourceNode to the destination
source.connect(audioCtx.destination);
button.onclick = () => {
const active = button.getAttribute("data-active");
if (active === "false") {
button.setAttribute("data-active", "true");
button.textContent = "Remove compression";
source.disconnect(audioCtx.destination);
source.connect(compressor);
compressor.connect(audioCtx.destination);
} else if (active === "true") {
button.setAttribute("data-active", "false");
button.textContent = "Add compression";
source.disconnect(compressor);
compressor.disconnect(audioCtx.destination);
source.connect(audioCtx.destination);
}
};
Specifications
| Specification |
|---|
| Web Audio API # dom-baseaudiocontext-createdynamicscompressor |
Browser compatibility
| desktop | mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
createDynamicsCompressor
|
|
|
|
|
|
|
|
|
|
|
|
|
Legend
Tip: you can click/tap on a cell for more information.
- Full support
- Full support