Adding an audio element to your page
The very first step is to add the audio element to your page. You can do this by declaring an <audio> tag in your markup, by instantiating a new audio element in the JavaScript code, or by embedding the audio stream in the page:
<audio src="audio/sample.mp3" autoplay>
</audio>
var audio = document.createElement("audio");
if (audio != null && audio.canPlayType && audio.canPlayType("audio/mpeg"))
{
audio.src = "audio/sample.mp3";
audio.play();
}
<audio src="data:audio/mpeg,ID3%02%..." autoplay>
</audio>
Loops
Another frequent request for scenarios with audio is the ability to loop a sound clip. With the HTML5 <audio>, you can do this using the “loop” property; this setting will loop your clip forever, or until the user or the application activates thepause() audio control.
<audio src="audio/sample.mp3" autoplay loop>
</audio>
Another approach to loop an audio file is to programmatically call the play() method when the audio clip ends; doing so will allow you eventually to manage the delay between one loop and the other.
var audio = document.createElement("audio");
audio.src = "piano/3C.mp3";
audio.addEventListener('ended', function () {
// Wait 500 milliseconds before next loop
setTimeout(function () { audio.play(); }, 500);
}, false);
audio.play();
Note that any play() call executed on the audio element before the sound actually ended won’t have any effect. If you are interested to “cancel and restart” the current sound, you will need to reset the currentTime.
var audio = null;
audio = document.createElement("audio");
audio.src = "piano/3C.mp3";
audio.addEventListener('ended', function () {
audio.play();
}, false);
function play() {
audio.play();
}
function restart() {
audio.currentTime = 0;
audio.play();
}
Multiple audio tags
If your scenario needs the same audio file to be played several times concurrently (that is, with overlapping sounds), you can achieve this result by creating multiple audio tags pointing to the same file. Obviously the same approach also works if you are using different audio files at the same time. As we explained earlier in this post, you can either add those programmatically or by instantiating them in the markup.
The following code snippet shows how to load and play multiple audio files using markup. The audio samples all have the same length; at the end of the execution, they will loop starting from the beginning. As you play them in Internet Explorer 9, you can notice that they are automatically synchronized throughout various loops. You will notice that the combination of these 5 sounds will play like the audio file used in the previous demo (“sample.mp3”).
<body>
<audio src="audio/Bass.mp3" autoplay loop>
</audio>
<audio src="audio/Drum.mp3" autoplay loop>
</audio>
<audio src="audio/Crunch.mp3" autoplay loop>
</audio>
<audio src="audio/Guitar.mp3" autoplay loop>
</audio>
<audio src="audio/Pizzicato.mp3" autoplay loop>
</audio>
</body>
While this approach is very simple and straightforward, in most scenarios developers prefer to create the audio clips programmatically. The following code snippet shows how to add 3 audio clips dynamically using code. As you play them together, you will get the C Major chord!
AddNote("3C");
AddNote("3E");
AddNote("3G");
function AddNote(name) {
var audio = document.createElement("audio");
audio.src = "piano/" + name + ".mp3";
audio.autoplay = true;
}
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