One problem in selecting classical music in many players consists of insufficent tagging options for classical music. On many CDs there are several compositions. If one uses the "album" tag for the name of the CD and the "title" tag for the individual tracks, there is no tag "in between" for the composition.
Example: a CD contains the compositions Symphony No.1 and No.2 from Beethoven. Each of these symphonies has four movements. The complete CD contains therefore 8 tracks which are represented by the "title" tags.
Now, I can select in the player the album which plays both symphonies or I can select a single track but which is only one of the four movements of a symphony. There is no way (other than using a playlist) to play a complete symphony (composition) directly.
In forums this problem is being discussed. On of the proposed solutions is using the "grouping" tag (in German the name of this tag is "Werk" which is corresponds exactly to the term "composition"). iTunes supports this tag in the newest release as well as MediaMonkey does. With these application it is now possible to select "Symphony No.1" and all four movements (tracks) of this composition are selected and played.
It would be extremely nice if the Sonos SW would offer the "grouping" tag as selection criteria besides the already existing options such as album, artist, genre, title etc.