Explore musical tunings and create synthesizer tuning files for microtonal scales.

Overview

tune is planned to be part of a larger ecosystem for microtonal software in Rust. So far, tune offers a CLI and an API with the following features:

• Pitch conversions
  • Convert between linear and logarithmic ratios
  • Determine the frequency for a given note in a custom tuning system
  • Determine the note for a given frequency in a custom tuning system
  • Find fractional approximations for frequency ratios
• Export scales
  • To Scala (scl and kbm) format
  • As Midi Tuning Standard (MTS) Sysex Messages

API documentation

Installation

bash cargo install -f tune

Usage

Create scl files

• 12-TET bash tune scl equal 1:12:2 tune scl equal 100c
• Bohlen-Pierce bash tune scl equal 1:13:3
• Equal temperament with step size of 5 sixth tones bash tune scl equal 5:36:2 tune scl equal 5/3:12:2 tunc scl equal {500/3}c
• 7-note Pythagorean (lydian mode) bash tune scl rank2 3/2 6 tune scl rank2 1.5 6
• 7-note quarter-comma meantone (major mode) bash tune scl rank2 1:4:5 5 1
• 8-note harmonic series bash tune scl harm 8
• Custom just intonation scale bash tune scl cust -n "Just intonation" 9/8 5/4 4/3 3/2 5/3 15/8 2

Create kbm files

• Start scale at C4 at its usual frequency bash tune kbm 60

• Start scale at C4, 20 cents higher than usual bash tune kbm 60+20c

• Start scale at A4 at 450 Hz bash tune kbm 69@450Hz

• Start scale at C4, A4 should sound at 450 Hz bash tune kbm -r 60 69@450Hz

Dump pitches of a scale

• 7-note Pythagorean (D dorian mode) bash tune dump 62 rank2 3/2 3 3 Output: ```bash ..

  62 | 293.665 Hz | MIDI 62 | D 4 | +0.000¢ | 1/1 [+0c] (+0o) 63 | 330.373 Hz | MIDI 64 | E 4 | +3.910¢ | 9/8 [+0c] (+0o) 64 | 348.047 Hz | MIDI 65 | F 4 | -5.865¢ | 6/5 [-22c] (+0o) 65 | 391.553 Hz | MIDI 67 | G 4 | -1.955¢ | 4/3 [+0c] (+0o) 66 | 440.497 Hz | MIDI 69 | A 4 | +1.955¢ | 3/2 [+0c] (+0o) 67 | 495.559 Hz | MIDI 71 | B 4 | +5.865¢ | 5/3 [+22c] (+0o) 68 | 522.071 Hz | MIDI 72 | C 5 | -3.910¢ | 16/9 [+0c] (+0o) 69 | 587.330 Hz | MIDI 74 | D 5 | +0.000¢ | 1/1 [+0c] (+1o) .. ```

• As JSON bash tune jdump 62 rank2 3/2 3 3 Output: json .. { "key_midi_number": 62, "scale_degree": 0, "pitch_in_hz": 293.6647679174076 }, { "key_midi_number": 63, "scale_degree": 1, "pitch_in_hz": 330.3728639070835 }, ..

• Conversion between scales: What are the pitch differences between Pythagorean and quarter-comma meantone tuning? bash tune jdump 62 rank2 3/2 3 3 Output: ```bash ..

  62 | 293.665 Hz | MIDI 62 | IDX 0 | +0.000¢ | 1/1 [+0c] (+0o) 63 | 330.373 Hz | MIDI 63 | IDX 1 | +10.753¢ | 9/8 [+0c] (+0o) 64 | 348.047 Hz | MIDI 64 | IDX 2 | -16.130¢ | 6/5 [-22c] (+0o) 65 | 391.553 Hz | MIDI 65 | IDX 3 | -5.377¢ | 4/3 [+0c] (+0o) 66 | 440.497 Hz | MIDI 66 | IDX 4 | +5.377¢ | 3/2 [+0c] (+0o) 67 | 495.559 Hz | MIDI 67 | IDX 5 | +16.130¢ | 5/3 [+22c] (+0o) 68 | 522.071 Hz | MIDI 68 | IDX 6 | -10.753¢ | 16/9 [+0c] (+0o) 69 | 587.330 Hz | MIDI 69 | IDX 7 | +0.000¢ | 1/1 [+0c] (+1o) .. ```

Create a Midi Tuning Standard Sysex message

• 19-TET bash tune mts 69 equal 1:19:2 Output: bash 0xf0 0x7f 0x7f 0x08 .. 0x7f 0x00 0x00 0xf7 Number of retuned notes: 127 Number of out-of-range notes: 0

Expressions

Ordered by precedence:

1. <num>:<denom>:<int> evaluates to int^(num/denom)
2. <num>/<denom> evaluates to num/denom
3. <cents>c evaluates to 2^(cents/1200)
4. {<expr>} evaluates to expr