How to add .WAV or mp3 music to your Google Site
First, create a new “File Cabinet Page” for your music files.
Upload your .wav or mp3 files to this page
Go to the page you would like your music to be on and copy this code onto your clipboard.
Search for Google Audio Player
Now, go back to the page you created where your music files are.
Over the word that says download, right click and “copy link address”
Go back to the page where you would like to play the music from.
Paste the link into the URL box
Okay and Save
We use the Google Audio Player to embed a MP3 player in a site.
(when you search for it in Site gadgets, it's easier if you put the
quotes around it: "Google Audio Player") We just upload the mp3 as an
attachment on the page, right click to copy the link then paste that
link into the player. It seems to work in Safari as well.
It's how our music students hand in their assessments. Here's the page
describing how we did it.