CREATIVE USE OF GROUPSITE TO LIMIT ACCESS TO MP3 FILES

In our Empathy World Groupsite community, we want to provide a number of our archived mp3 class recordings to members but want to restrict some recordings for only SOME members. . .

Is there a way of doing this on our Groupsite? Through File Cabinet? Or somewhere else on Grouptsite? Perhaps have some recordings password protected? or having it restricted in some other way?

Also thinking that you might know of a service, a site or a software that can do this--get this done for us (?). Perhaps compatible with Groupsite if needed.