How to filter down entries of a specific item tree

[Wolfgang]

I wonder how I can mange that under the tree "Composer" only my classical music titels show up.
My music server holds pop music and classical music as well. On one hand I see little use for drilling down by Composer when searching for pop music. On the other hand the Composer item is essential for classical music. But I don't want to dig through thousands of composer names from pop music titles.

What would you suggest to get the desired behaviour as close as possible?

thanks for recommendations in advance!
Wolfgang