.csv

The .csv file extension designates a general format for any data in a comma-separated list of values. The format has been in use for tuning files since 2005 for lists of MIDI Notes with Pitch Bend data in decimal form. In a .csv file, there is no information concerning a scale as such. This format is supported by all H-Pi Instruments tuning software. The specification is as follows:

.gly

The .gly file is a binary file created by Native Instruments Absynth software. There are no public details on this file type. The file data is an encoded list of 128 Hz values, one value per MIDI note, containing no scale data as such.

.hz

The .hz file extension was introduced in 2009 with H-Pi Instruments software synthesizer H-Pi Lo-Fi Microstudio (HPLF) to designate a simple list of frequencies in Hz. A .hz file contains no information about a scale as such. The specification is as follows:

.mts

The .mts file extension is sometimes used as an alternative to the .syx extension to designate a binary file containing a MIDI Tuning Standard sysex message.

.mtx

Files in the .mtx format are created by Max Magic Microtuner software by Victor Cerullo, introduced in 2003. A specification is available as a PDF and also as an HTML page containing code examples for its implementation.

.scl

The most widely used tuning file format is the Scala .scl file, designed by Manuel Op de Coul in 1992. The specification for the .scl file is maintained at the Huygens-Fokker website. A separate format called a Keyboard Map, having the extension .kbm, can be used to assign scale tones to MIDI keys.

.syx

The .syx file extension is not specific to tuning, but rather designates a MIDI Sysex binary file. When a tuning file is given the .syx extension, this implies that it contains a MIDI Tuning Standard sysex message. The specification for the MIDI Tuning Standard is available from the MIDI Manufacturer's Association (MMA).

.tonex

This file type was introduced in 2009 along with the TuningXML language. In a .tonex file, xml tags specify different aspects of a tuning.

.tsv

The .tsv file extension designates a general format for any data in a tab-separated list of values. The format is suggested as a tuning file for lists of MIDI Tuning Standard frequency data in decimal form. The specification is as follows:

  • 8-Bit ASCII text, text encoding is ignored
  • 3 values per line: MIDI Note, Tuning MSB, Tuning LSB, followed by a line ending
  • Files may be 128 x any multiple between 1 and 16 lines long, for full-range tunings up to 16 MIDI channels in ascending order, 128 notes per channel

.tun

A popular tuning file format used with VST instruments is the AnaMark-TUN .tun file, designed by Mark Henning in 2003. There are two versions of this file format, the first of which is quite simple, and the second of which allows for a wide range of sophisticated options partly based on the development of TuningXML. The majority of these files consist of a list 128 cents values. The cents values are given in reference to the lowest MIDI note 0, and this form of the file contains no scale information as such. The specification is available as a PDF with code samples and further information downloadable from this HTML page.