playthrough.html

<!DOCTYPE html>
<html>
    <head>
    </head>
    
    <body>
    <script>
        function error() {
            alert('Stream generation failed.');
        }

        function getUserMedia(dictionary, callback) {
            try {
                navigator.webkitGetUserMedia(dictionary, callback, error);
            } catch (e) {
                alert('webkitGetUserMedia threw exception :' + e);
            }
        }

        function gotStream(stream) {
            var context = new AudioContext();

            // Create an AudioNode from the stream.
            var mediaStreamSource = context.createMediaStreamSource(stream);

            // Connect it to the destination.
            mediaStreamSource.connect(context.destination);
        }

        getUserMedia({audio:true}, gotStream);
    </script>
    </body>
</html>