Torus is a system for organising and identifying tunes without knowing their titles. It works by indexing the tunes according to their shape, i.e. according to how they go up or down in pitch from each note to the next. This sequence of jumps up or down is represented as a string of us and ds, and this string is used to locate the tune in the index. Thus provided you can hum, whistle or play the tune you can find its title - it doesn't matter what key it's in, and you don't even need to be able to identify the intervals accurately. Here are some more details, and an example.
The Torus database contains information about mostly English and other folk music tunes. It has 1898 versions of 1540 tunes with 1926 titles, with 1923 references to 44 sources, and it can resolve these completely using an average of 12.9 characters. I'm very grateful to Bob Archer for contributing a large chunk of tune data, based on work done with Eric Foxley and Philip Rowe. The database was last modified on 25 November 2018. It's available for download as a CSV file (172.0 kB) or zip file (44.4 kB), and some information about the data format are also available. Please respect the distribution conditions.
For those times when you don't have a web browser handy there's an Android mobile phone version. I no longer maintain the original hardcopy booklet version, but if you're still interested in it then please contact me.
This page is maintained by Thomas Bending,
and was last modified on 25 November 2018.
Comments, criticisms and suggestions are welcome. Copyright © Thomas Bending 2018.