Scale library

A library of microtonal scales with sources attributed.

The scales directory contains the scl files for each scale. The scl files are also available for download as a zip on the releases page. The library currently contains 2478 scl files.

Sources

The scl files are generated from the following sources:

Mailing lists: 1329 scl files

The scales/mailing-lists directory contains scl files extracted from the Yahoo tuning groups ultimate backup, an archive of several tuning related mailing lists. Each scl file includes a URL for the message containing the scl file on the Yahoo tuning groups ultimate backup website, which allows browsing the mailing lists in a readable form. For example:

! xenoga24.scl
!
Xeno-Gothic rational adaptive tuning, 3-7 ratios (keyboards 64:63 apart) 
24
!
 64/63
 2187/2048
 243/224
 9/8 
 8/7
 32/27
 2048/1701
 81/64
 9/7
 4/3 
 256/189
 729/512
 81/56
 3/2
 32/21
 6561/4096
 729/448
 27/16
 12/7
 16/9
 1024/567
 243/128
 27/14
 2/1
!
! https://yahootuninggroupsultimatebackup.github.io/tuning/topicId_16640.html#16640
!
! [info]
! source = Mailing lists
! file = tuning/messages/yahoo_tuning_messages_api_raw_0-19436.json
! topic_id = 16640
! msg_id = 16640

DaMuSc: 426 scl files

DaMuSc is a database of musical scales. It contains cent values for many theoretical and measured scales from around the world, along with references to their source. The scales/database-of-musical-scales directory contains scl files generated from the measured scales in the DaMuSc database, each containing the reference to the scale's source. For example:

! Georgia_GVM206-M.scl
!
Measured scale M0311 in DaMuSc
 7
!
 179.0
 358.0
 500.0
 701.0
 887.0
 1067.0
 1189.0
!
! N. Mzhavanadze and F. Scherbaum. Svan funeral dirges (zar): Musical
! acoustical analysis of a new collection of field recordings.
! Musicologist, 4(2):138-167, 2020. doi: 10.33906/musicologist.782094
!
! [info]
! source = DaMuSc
! measured_id = M0311
! ref_id = 56

Divisions of the Tetrachord: 723 scl files

John Chalmers' book Divisions of the Tetrachord, available online here, contains a catalog of tetrachords in chapter 9. The scales/divisions-of-the-tetrachord directory contains scl files for each of the tetrachords in the catalog. For example:

! 475_D17.scl
!
Diatonic tetrachord 10/9 * 10/9 * 27/25, Al-Farabi
 3
!
 10/9
 100/81
 4/3
!
! Chalmers, John H. Divisions of the Tetrachord.
! Frog Peak Music, 1993.
!
! [info]
! source = Divisions of the Tetrachord
! catalog_index = 475

An example

While setting up this library, I searched it for a scale similar to a version of Maqam Rast I use (with a second of 10/9 to make it easier to play on my guitar). I was very happy to find my scale was within four cents of the DaMuSc scale Georgia_GVM206-M.scl given above. The reference for the scale was to an open access paper, which introduced me to this wonderful archive of videos and recordings from Georgia. In the archive I was able to watch a video of the very performance from which the Georgia_GVM206-M.scl scale was extracted. This is exactly the sort of thing I was hoping the references for the scales would do - I hope it happens often!

And it turns out my scale is built from a tetrachord which is within three cents of the tetrachord due to Al-Farabi in 475_D17.scl above. Divisions of the Tetrachord gives examples in the same genus from Ptolemy and Avicenna.

Also my scale is within three cents of the seventh mode of the scale in synpor4.scl from the tuning-math mailing list. The linked email gives related scales which are all Fokker blocks according to the subject.

Other scale libraries

These great scale libraries may also be of interest:

• The tunings in Leimma. These all come with sources attributed.
• The Scala scale archive
• Wilson's garden, a scale collection built into Wilsonic
• The tuning library included with Surge XT
• Ableton comes with a library of tunings