How to choose a specific audio output device in Firefox or Chrome?

Question

I'm building a low-latency sampler in the browser (using Javascript, WASM, etc.).

How to choose, from Javascript, a specific audio output device for Chrome or Firefox?

I see there is Audio Output API but there are not many examples (and by the way navigator.mediaDevices.selectAudioOutput is undefined on my Chrome 109).

For example, how to make Chrome use Asio4All as main output device?

(Note: using an ASIO device such as the free Asio4All driver can make the latency drop from 30 milliseconds to 5 milliseconds, even on an old computer).

Answer 1

There is also Audio Output Devices API which can be used to achieved the similar functionality.

// First Create a new audio element
    var audio = new Audio("https://samplelib.com/lib/preview/mp3/sample-3s.mp3");
    
    // Get the list of available audio output devices
    navigator.mediaDevices.enumerateDevices()
      .then(function(devices) {
        // Filter the devices to get only the audio output ones
        var audioOutputDevices = devices.filter(function(device) {
          return device.kind === "audiooutput";
        });
        // Log the devices to the console
        console.log(audioOutputDevices);
        // If there is at least one audio output device, use the first one as the output device
        if (audioOutputDevices.length > 0) {
          // Set the sink ID of the audio element to the device ID of the first audio output device
          audio.setSinkId(audioOutputDevices[0].deviceId)
            .then(function() {
              // Play the audio
              audio.play();
            })
            .catch(function(error) {
              // Handle any errors
              console.error(error);
            });
        }
      })

The audioOutputDevices[] can be leveraged to choose between vaious output devices.