If you choose to put these .js documents on your server it is imperative that you always have the most current version. An easy way to avoid this little maintenance chore is to have your .html documents pull the JavaScripts off of Beatnik's server.
All you have to do is paste this bit of code just below the <body> tag in your .html document:
<SCRIPT SRC="http://sonify.beatnik.com/music-object.js"></SCRIPT>
This way every time someone views your page their browser will go to Beatnik's server and grab the needed up-to-date source code.