My mp3s are animals sounds, rain sounds... that I converted or modified from Youtube. I think they are public but I'm not sure.Would depend on the content of said mp3s - what you are proposing could land you in some very hot water if the music isn't public domain (anybody can use, share and transfer without penalty).
You should be ok then if that's all they are. I mean it's pretty hard to copyright animal and weather sounds etc, but then Apple have trademarked rectangles with rounded corners.
All you need really is some form of general file hosting along with a domain - unless you have it link to a shared space on some form of cloud storage.