Classical compositions and your MP3s
Pretty early on, a lot of digital music owners recognise that organising classical music libraries is a pain. By and large, music players don't support classical music as well as contemporary forms of music. Typically, music player browsing is built around the concept of artists and albums, whereas classical music recordings tend to be classified by composers, performers and compositions.
I'm going to be all stereotypical and generalist and say I think this is because of the traditional demographic that was enthused by digital music: the young and techno savvy (yes, I know there are exceptions!). Over time, though, digital music has become more mainstream, and the amount of digital classical music is increasing.
Whatever the cause, if you have classical music in your digital music collection then you want it organised and browsable in the most efficient manner. Organising this music requires the embedded metadata within your music be complete, consistent and correct. Now, let's separate this metadata into two parts: (1) the persons involved in a given classical recording and (2) the classical composition itself.
I already covered composers, performers and conductors in a previous blog post. In this blog post I'll be looking at ways of organising the different granularities of classical compositions, that is, concentrating on how the composition itself is stored.
The usual warning about music player support...
But I'll start with a warning. I said right at the top of this article that many music players don't support the classical concepts of composers, conductors, symphony or movement. For instance, when browsing your music you may see no option to see all performances involving the conductor Simon Rattle. Well, if that is the case for your music player then the tips here will only be of limited use. Your music player is king and dictates how you should organise your music. Specifically, this article discusses use of the CONTENTGROUP tag (and synonyms for different tagging formats) so your music player must support this tag.
Raspberries go to Windows Media Player, which does support the tag, but uses it to store subgenre information. This is ok if you only use WMP, but portability to different music players will be compromised.
Anyway, "on with the show". How should classical compositions be structured?
There are two main levels to a classical composition. The first is the composition itself. This can be any of the grand, large form orchestral works such as a symphony or concerto. Alternatively, it can be those that are of a generally smaller scale, such as a nocturne or a prelude.
Within a composition, you have movements. There are certain formats that movements are supposed to take, given the style of composition, but these rules are quite often broken. Movements have names like Andante and Allegro referring to the pace or tempo of the music.
Also, not of the composition itself but still important in terms of organisation is the encompassing 'release'. That is, the album, CD or collection grouping these performances together. This is important for things like CD art.
Now, these levels of granularity can be applied to digital music tagging. We need three levels of granularity, and then we can map them to each of the main tagging formats. Release and movement take up the familiar album and track name tags, while composition is generally shuffled into what is known generically as the content group tag:
|MP3 and MP4 (ID3v2.x) (.mp3, m4p, .m4a)||TALB||TIT1||TIT2|
|Ogg and FLAC (.ogg, .flac)||ALBUM||TITLE||PART|
 - This is the generally accepted recommendation, but many music players will not show the PART tag. This will have the effect of showing four tracks with the same name: that of the composition. A workaround is to append the movement to the composition name in the TITLE.
Your trusty music tagger may represent these field names slightly differently - refer to the guides for your specific tagger.
What about opus numbers? Well, Vorbis comments allow for an OPUS tag and ID3 tagging has TIT3, which can be used for 'subtitle'. However, opus numbers themselves can be arbitrary. Some were dictated by the composer, some by the publisher to groups of compositions and in some places they contradict one another. If you want to record this information use the TIT3 or OPUS tag.
If you're going to group, group properly
If you own a music player that shows all entries for the content group tags, then you need to make sure the grouping is made consistently.
The content group tags need to be used just for grouping classical composition. Some people use these groupings for all manner of other reasons: record company, parental guidance rating and more. It's always best to use one tag for one purpose. You can normally add user defined tags for other purposes.
That got pretty heavy! I hope, combined with my tips on composers, performers and conductors, this post will help you tag your classical music to make it easier to find, navigate and choose to play.
Thanks to lemonjenny for the image above.