|Status: This page describes an active style guideline proposal and is not official.|
Definition of a classical work
Works belonging to the "classical music" genre should either have at least one known recording or performance (even if it is not currently in the MB database) or should be the most recent common ancestor to two Works which are in the MB database.
Works should be entered into MusicBrainz using the boundaries decided by the composer, as printed in the score.
Note: Do not split a musical entity into smaller pieces based on tempo markings, lyrics or other information. E.g. the fourth movement of Beethoven's ninth symphony contains many musically different sections, but it is still only a single work.
In unnumbered operas (Wagner, for instance), sometimes an act is the smallest entity you can enter. See "excerpts" below for how to deal with popular arias and choruses.
The recommended structure for opera is: Number is a part of Act is a part of Opera (Number and Act are of course optional)
Note: Be careful with "scenes" (information about what is happening on stage). Do not add "Scene" to the "folder structure" (Number is a part of Scene is a part of Act...) even if it could be viewed as technically correct.
Sometimes works are published in "collections". This is common for songs and shorter instrumental pieces, but can also happen with larger works like piano sonatas. These works can be interesting to have as "containers", but should not be treated as a main work with parts.
Note: In general you should only add a collection if the composer was involved. Do not enter things like "All piano sonatas by Beethoven" as works in MusicBrainz.
If you a work has specific versions (examples listed below), make sure that there is also a "basic" version available. You will not always be able to source what specific version is performed.
Note: Do not add a disambiguation comment saying "unknown version". It is implied that a work that is not a specific version should be connected to all performances where it is unclear which version has been used.
Different revisions of a work by one single composer. The most common case is when an earlier work is edited for a performance some years later.
For written (and published) arrangements of another work. Here "arranging" is defined as changing the harmonies in the music, and/or rewriting the work for a different type of ensemble, for example from piano and soloist to orchestra.
Do not create a new work for improvised arrangements, "head-arrangements", private / unpublished arrangements or when the arranger is unknown. For an arrangement to be valid as a unique work in MusicBrainz, it must be possible for other performers to record new versions. There must be at least two different recordings available. The recordings must be of different performances by two different (groups of) performers. You must be able to source that the both performances use the exact same arrangement. If in doubt, do not create a new work.
For every other case, use the recording - artist arranger relationship.
Note: Works can always be performed with different instrumentation than indicated in the score, and solo parts can be supplied for different instruments or voice ranges. This does not merit a new work.
Note: Usually the arranger will not be given composer credit for the arrangement work, but exceptions do exist. Follow the general praxis.
Linking recordings to works
It is possible that you have found the correct works to link to your recordings, but it is not an exact match. This is usually solved with the performance AR. If the recoding contains more than one work, link to all performed works. If the recording contains just a part of a work, use the "partial" attribute.
There are however some cases that can be treated differently:
Complete multi-part works
If a multi-part work is presented as a single recording, you can link the recording to the "container" work, instead of linking to every sub-part.
Menuet I - Menuet II etc.
Strictly speaking these works are a single musical entity, but if the "second part" is often recorded as a standalone piece, it can have its own work.
Note: Do not routinely create split works. This is most common for instrumental solo works.
If a sub-part of a larger work is performed regularly as a standalone piece, you can add it as a work.
Note: Do not add more than one work per excerpt. For instance, there should be only one "Ode to Joy" from Beethoven's ninth symphony, even if the amount of bars from the symphony that are actually performed differs between individual recordings.
Note: Do not confuse audio excerpts (edited recordings) with a deliberate performance of an excerpt.