It is impossible if you post

because most of people know how to find the link (codes)from your source code.

The only possible way is to create a html page in other web site, where you embed your music, and then you use IFRAME codes to post that html page here so that when we open your page and check the source codes, we can only see IFRAME codes.

Otherwise, just use "hidden" in the followinng place indicated by ******
"embed src="http://" ****** width=300 height=40 controls=ControlPanel loop=true autostart=true volume=100 type=audio/x-pn-realaudio-plugin Initfn=load-types mime-types=mime.types "