I just spent the past weekend re-tagging the genres on all my music. My music tagging system has gone through several variations over the years and something in my brain hasn't let me stick with one system for too long for one reason or another.
When I originally started tagging music I would put bands into what seems like the most appropriate genres. So I had genres like Hard Rock, Symphonic Power Metal, AOR, Funk, Film Noir Jazz, etc. Keep in mind I also used genres as my top level directory for folders at the time too. You can see early on how this is going to start sucking in the future.
That seemed okay but then I wanted all the top level genre tags by each other so I reversed the order of the tags so that Symphonic Power Metal became Metal - Power - Symphonic. By going from most broad to most explicit, all my top-level genres were organized and each style was right by each other, drilling down nicely in a list, for example:
Electronic - Trance
Electronic - Psytrance
Metal - Death
Metal - Death - Melodic
Metal - Power
Metal - Power - Symphonic
Rock - Alternative
Rock - AOR...
and so on.
This was okay for a while too but at this point I was really tired of using folders to organize so I just started putting everything under 1 directory using "artist\year - album" as the folder structure and use music library software to rearrange tags. It was also about that point that I started to get sick of tagging stuff as Gothic Folk Metal or whatever so I started consolidating tags into stuff like Gothic/Doom, Viking/Folk and Progressive/Power so I would only have a few major sub-genres. It sort of solved a problem I had wherein I didn't know what to classify bands that have crossover tendencies with say, Progressive Metal or Power Metal. It completely sidestepped a kind of philosophical problem as to what the top level genre should be for a band that you could call both Progressive or Power. I had 1 genre for both. But what about a band that has both Power and Thrash elements? Where do I put them? I had to make compromises for the sake of cleanliness.
Another problem I had was, what about bands that significantly changed their sound as they evolved? Would I just continue tagging them as what they originally sounded like or would I make the concession that bands do evolve and change (since there are really people making this music and people grow in uncountable ways as they live and create)? I have been just keeping all albums of a band under whatever genre they started out as for the sake of simplicity rather than accuracy.
Time for a new evolution.
I discovered that Foobar2000 (my current player/library management software) allows for multiple genres that you can separate with semicolons. This has opened up a new way of thinking about music classification. No longer do I have to put the band Prototype under Progressive/Power. I can put it under both Power and Thrash and it'll show up under either one when I select the genre. I have solved the problem of genre bending music. I can just give any album any tags that fit without having to conform to a rigid set of rules that I had previously established for classification. This applies also to the problem of bands with sounds that evolve. I don't have to put Nightwish under just Symphonic Power Metal anymore. I can put their early albums there but I can put their new stuff under Symphonic Metal as they've pretty much completely dropped all Power Metal elements from their music.
What if I want to listen to music from a certain era? Or a certain country? Or a combination of eras, countries, top level genres and sub-genres? I can do all of that. As I said at the beginning of the thread, I spent all day yesterday re-tagging my files. My genre tag for songs now looks like this:
-era-; Genre; [sub-genre]; [sub-genre]; (Country) for example:
-1980s-; Rock; [Pop Rock]; [AOR]; (USA) for Toto IV
This way that album will show up under a filter for any of those tags. It makes it much more intuitive for me to find music I want to listen to at any given moment. It's much less rigid. It flows better.
The way I classify my music is an ongoing evolution that is much like the evolution of the music I listen to itself. As I change my mind about things and I see how musicians change their minds about how they make music it becomes clear that musical classification and identification is not something static. It is a moving, changing entity itself.