Chanofreq Project

Objective: The Chanofreq project aims to develop a standardized file format that allows precise tuning of each note on every MIDI channel to a specific frequency, using a minimalistic data structure.


File Extension: .cnf

Format Name: Chanofreq

Etymology: Derived from Channel, Note, and Frequency.

File Structure

A Chanofreq file is a text file containing commands with the following structure:

channel X note Y frequency Z
  • X: An integer ≥ 1, representing the MIDI channel.
  • Y: An integer ≥ 0, representing the note number.
  • Z: A 64-bit floating-point number > 0, representing the frequency in Hertz.

Commands can be separated by a semicolon (';') or a newline.

Examples:

channel X1 note Y1 frequency Z1; channel X2 note Y2 frequency Z2
channel X3 note Y3 frequency Z3

Syntax

To define tuning for instruments controlled via MIDI, use:

channel X note Y frequency Z

For instruments with internal notes not controlled by MIDI (such as those with built-in sequencers or keyboards), use:

internal note Y frequency Z

To set a fallback frequency for any unspecified note Y across all channels and internal settings, use:

default note Y frequency Z

Comments:

Inline comment:

/* Inline comment */

Multiline comment:

/* Multiline
comment */

Behavior on Loading

Upon loading a Chanofreq file, all notes start in an inactive state. As the file is read, each channel and internal command activates the specified note and assigns it the corresponding frequency. If a note that is already active is specified again, its frequency is updated to the new value provided. The same process applies to any default settings defined in the file. After processing the entire file, any notes that remain unspecified are assigned the default frequency if one is set. If no default frequency is provided, these notes remain inactive.

Development Roadmap

  1. Web Interface: Develop an online tool for easily creating .cnf files.
  2. Virtual Synthesizer: Build a basic virtual synthesizer supporting .cnf format to serve as a reference implementation for developers.
  3. Presentation Video: Produce an engaging video to introduce the .cnf format and demonstrate the synthesizer, aimed at persuading developers and users of its utility.
  4. Collaboration with Oddsound: Partner with Oddsound to integrate the .cnf format into their MTS-ESP Mini and MTS-ESP Master plugins.
  5. Update Xen Wiki: Add a "Multi-Channel Tuning Ability" column to the List of Microtonal Software Plugins, highlighting developers who properly implement the .cnf format or MTS-ESP Multi-Channel.
  6. Advocacy: Promote the adoption of the .cnf format and MTS-ESP Multi-Channel among tuning-friendly companies, as detailed here and here.