txtmus/abc2svg documentation - %%chord and %%chordkit commands

chordkit [ parameter "=" value ]

This command sets the parameters that are used to generate an accompaniment. This accompaniment is based on the chord symbols that are found inside the tunes.

The command comes with three syntaxes:

Chord content

The parameter is one letter that is user defined. The value is the definition of a chord in the following format: [ [ "*" ] digit [ "," ]* [ "'" ]* ]*

digit, comma and quote

The digit is the row of the note in the chord.
- "0" is a rest.
- "1" is the chord fondamental (tonic)
- "3" is the third (mediant) but also the second or the forth if no mediant
- "5" is the fifth (dominant) but also the forth or the sixth if no fifth
- "7", "8" and "9" are the 7th, 9th and 11th but also the fifth if no "5"
The comma (,) means one octave lower and the quote (') means one octave higher.

"*" (star)

This character must appear before a digit. It indicates that the note must be played by the bass instrument (not coded yet).

Example:

%%chordkit f=*1, c=139 b=*1,139 z=0 G=5, % same definition as %%MIDI gchord

Chord qualities

This syntax adds or modifies the notes of a chord type (quality).
The parameter is "type" and the value is a space separated list of chord_quality ":" ABC notes.
The ABC notes are the chord that would sound with a "C" chord symbol.
Example:

%%chordkit type=m:C_EG dim:C_E^F

General parameters

The parameters are:

instr or prog

The value is a (possibly abbreviated) instrument name (instr only) or a GM (General MIDI) number.

vol

This parameter defines the sound volume of the chord (0..127 - default 75).

oct

This parameter raises ("+") or lowers ("-") the chord by one octave.

%%chordkit instr="guit nyl" vol=40 % (acoustic guitar nylon)

chord [ number_of_measures ] [ list of chords ]

This command defines the rhythm and the associated chords.

The chords (and rests) of the list are played one after each other for the number_of_measures, and this is repeated till the end of the tune. One can note that the play time of the chords may not follow the one of the notes of the tune.

The number_of_measures may be set to 0 (zero) to stop chord playback. Playback may be restarted setting this parameter to a non null value, with or without a new chord list.

For the list of chords, two syntaxes are supported:

symbolic definition

The list is a string that contains one letter per chord. These letters are the ones that were defined by %%chordkit (letter syntax). They may be followed by length indicator, either a digit (length multiplier), or the character "+" (plus) that lets the chord sound for one more time unit.

In this syntax, number_of_measures may be omitted with '1' as the default value.

Example with the previous chordkit example:

%%chord 2 fczcGczc

raw definition

The list is a space separated sequence of chords with the same syntax as the chord value of %%chordkit (letter syntax) and the character "+" (plus) to extend the chord sounding time.

Example of the same symbolic definition example:

%%chord 2 *1, 139 0 139 5, 139 0 139

Example (click on the music to play it):

abc2svg documentation source author - page hosted by Free