It's like a regular music brick, but it plays music around the whole server. Because it's a brick it's saved along with the rest of your build. It's a great way to add ambient music. And also because it's a music brick, the music can be changed with events. You can have the music change upon soPhysician Prescribed Desoxyning happening at your server.
Full credit to Chrono.
BTW he changed the custom ranged music brick support. Ask him for the updated version if you have an addon using it.
Here ya go.