Bear in mind that the situation you describe is complex enough that vendors such as Hyland sell software up into the six figure range (OnBase) to do exactly what you describe. This is a basic document management situation, even if the "document" is an audio file. If you don't want to use filestream, you'll have to code a custom app to locate the file in the filesystem and then store the metadata in the database, same as any other document management system. There's nothing out of the box for SQL other than filestream to manage something like this.