Essential metadata for music libraries

Metadata in digital music is used to describe the contents of an audio file. Without metadata we would need to rely on the filename or listen to the song to identify it.

Information about a song might have once been confined to the radio studio. Now it could be on radio station websites, apps, RDS and scrolling text on DAB. If a station uses visual radio it might appear in a lower third.

The data could also be used in ways we’ve not yet thought of. Accurate metadata will be necessary when someone asks their smart speaker to find a radio station that plays Taylor Swift.

Updating the metadata in a music library or database can be a mammouth task. It’s certainly easier to get the metadata right when building a library from scratch.

Before building a music library or database it’s worth thinking about the metadata that is required. Applying consistent rules when a decision needs to be made about a field is also important.

Finding accurate metadata

When music is downloaded as an MP3 or FLAC file it often comes with metadata. The same applies for music which is ripped from a CD.

The quality of the metadata can vary, especially for older songs. Albums are rereleased or remastered and a song from the 1960’s can end up with a year tag of 2006. If the metadata was submitted by a user there could be typos, mistakes or completely wrong metadata. Anyone who used free CD ripping tools in the early 2000’s might remember having to correct it.

It’s useful if as much of the metadata as possible can be accurate when it is ripped. This saves time later on. A good way to do this is with dedicated CD ripping software like dBpoweramp.

When fixing metadata or tags a good source of information is MusicBrainz. Artist and band pages can be retrieved with a simple search. The pages list singles, albums and other releases. Although the information is accurate, it’s still worth checking the release dates. “Changes” by David Bowie has a release date of 1990 due to the CD version of Hunky Dory being released that year, but the album’s original release was in 1971.

Essential metadata fields

In this post the terms music library and music database will be interchangeable, assuming that any items in a music database are stored digitally.

Below we’ll look at the essential fields when adding songs to a music library. You’ll likely need to set other tags in your playout or music scheduling software, but this will be covered on another page.

Title

The title of the song - e.g. “Shake It Off”.

There are sometimes multiple versions of a song. You can decide whether to include the version - e.g. “Shake It Off (Album Version)” or “Shake It Off (Radio Edit)”. If it’s not important to the listener consider the simpler title and note the version in the filename or comments. If the song is different to the most popular version, consider using the full title, e.g. “So In Love With You (Pizzaman House Mix)”.

Some titles come with a featured artist, such as “Bad Blood (feat. Kendrick Lamar)”, when downloaded or ripped from a CD. On MusicBrainz and an ISRC database the title is trimmed to “Bad Blood”.

For presenters choosing between the 4:43 and 8:57 versions of “November Rain” by Guns N’ Roses it should be clear in the playout system which are the single and album versions.

Songs titles might also contain (Acoustic) or (Live).

Artist

The artist that released the song - e.g. Taylor Swift.

This is normally straightforward, but there are some cases where a popular artist has extra information in this field. “Get Back” is credited to The Beatles with Billy Preston while “Just Dance” is by Lady Gaga featuring Colby O’Donis.

Collaborations in the last few years have given us some long artist and title fields. The track “Feels” is by Calvin Harris feat. Pharrell Williams, Katy Perry & Big Sean. Sometimes this information pops up in the title or artist field. It might be ‘feat’, ‘featuring’ or a symbol.

Despite Aerosmith featuring prominently in the music video the song “Walk This Way” is credited solely to Run-D.M.C. “Back To Life (However Do You Want Me)” is by Soul II Soul feat. Caron Wheeler.

Some band names start with ‘The’. It’s important to be consistent with this field to help with music scheduling, as it may consider ‘Rolling Stones’ and ‘The Rolling Stones’ to be completely different artists. This will have the effect of songs not being scheduled according to artist repeat rules. The MusicBrainz page for The Pretenders shows some albums as being by Pretenders and others by The Pretenders.

Album

The album the song was released on - e.g. 1989.

Some songs don’t appear to have been included on an album when released. In this case you could repeat the title. The band Stardust only released the single “Music Sounds Better with You”, so the title of the song could be entered into the Album field.

Songs ripped or downloaded from compilation albums will have the album and year of the compilation. Consider whether you will adjust this tag to reflect the original album.

Year

The year the song was released - e.g. 2014.

An issue can occur when programming a programme or feature which relies on the year associated with a song. Some songs are released in one year but don’t chart until another. Songs released in late December might be much more associated with a long run in the charts the following year.

Some songs are released on an album in one year and as a single in the next year. To be consistent with the library it might be best to take a uniform approach to the release date and use additional sources when planning features around a specific year or decade.

Again, compilation and greatest hits albums will have the year of that release. If all of The Beatles songs in your library come from a CD rip of the 1 album, all of those 1960’s songs will sit in the library with a year of 2000 unless the tag is updated manually.

ISRC

The International Standard Recording Code - e.g. USCJY1431349.

A search tool is provided by IFPI to look up the ISRC.

Comments and Notes

This field should not normally be seen by anyone outside of the station. It’s an opportunity to add information about the song, both for on air links and internal information.

On air information might be the film soundtrack it appears on or the number of weeks it spent in the chart.

Internal information might be the version of the song, such as a particular radio edit or album version, or details of who added it to the library and when.

Added/compliance by AB on 12/03/2015. Ripped from 1989 album CD.

— Example comment for Shake It Off by Taylor Swift

Portability of metadata

Metadata can be saved in the MP3 or FLAC file, but also in the music scheduler or playout system. Transferring the data to another system in the future may be necessary.

Many file formats can store metadata. In MP3 files this is the ID3 Tag and the information is easily editable in applications like MP3Tag.

When music database applications and playout systems import items a copy of the data is often made. This means that changes made to the file are not reflected in the database and vice versa.

Fortunately many applications can import and export data in CSV files (and other formats). Moving from one system to another, or wishing to see the data in Excel or Google Sheets, can be made quicker with an export than accessing the information from thousands of individual files.

A note on filenames

Depending on your software the filename might be one you set or one which is chosen for you. Some playout systems import files and make their own copies with a filename like 12345.wav. Other systems use your original file and filename.

It might be worth renaming files to contain the artist and title which is in the metadata, e.g. Taylor Swift - Shake It Off.wav. Some applications can automate this process.

This makes files clearly identifiable without needing to see the metadata first.

Conclusion

Accurate metadata makes it easier to find and organise music in a library. It also makes it easier for listeners to discover your station and see what’s being played.

Spending time on metadata future-proofs your music database. An app or web service that hasn’t been invented yet might use metadata to help (potential) listeners in a way we haven’t yet foreseen.