Chord grids

In some European countries, particularly France, jazz musicians use so-called ‘chord grids’, which notate chords visually by placing them in squares.

Although they are omitted in the rest of this section for brevity, it is recommended to use the following \paper settings for chord grids:

\paper {
  indent = 0
  ragged-right = ##f
}

indent = 0 ensures that the first line is not indented as it would normally be (see \paper variables for shifts and indents). ragged-right = ##f is necessary for single-line grids to ensure they span the whole page; see \paper variables for widths and margins.

In order to create a chord grid, instantiate a ChordGrid context.

\new ChordGrid \chordmode { c1 d1:m e1:7 f1:7+ }

Each square is automatically subdivided.

\new ChordGrid \chordmode {
  c1
  d2 c2
  e2. c4
}

Chords spanning a complete measure are centered within their square. Chords lasting half a measure take half the square, and those lasting a quarter of a measure take a quarter of the square. This summary picture shows the default rules for subdividing the square:

The \medianChordGridStyle changes the default display of squares with particular measure divisions to use the style recommended by Philippe Baudoin in his book Jazz, mode d’emploi (“Jazz, user instructions”).

\layout {
  \context {
    \ChordGrid
    \medianChordGridStyle
  }
}

In chord grids, rests cause the noChordSymbol to be printed, just like in a regular ChordNames context (see Printing chord names).

\new ChordGrid \chordmode { c1 r2 c2 R1 }

Skips cause blank space. They can occupy part of a square.

\new ChordGrid \chordmode { c1 s2 c2 s1 }

Selected Snippets

Customizing the chord grid style

Custom divisions of chord squares can be defined through the measure-division-lines-alist and measure-division-chord-placement-alist properties of ChordSquare. These are both alists. Their keys are measure divisions, namely lists which give the fraction of the measure that each chord (or rest, or skip) represents. More precisely, a measure division alist is made of positive, exact numbers adding up to 1, for example: '(1/2 1/4 1/4). The exactness requirement means that, e.g., 1/2 is valid but not 0.5.

The values in measure-division-lines-alist are lists of lines, which are represented as (x1 y1 x2 y2). The line starts at the point (x1 . y1) and ends at (x2 . y2). Coordinates are expressed in the [-1, 1] scale relative to the extent of the square.

The values in measure-division-chord-placement-alist are lists of (x . y) pairs giving the placement of the respective chords.

This example defines a peculiar chord grid style that has a rule for measures divided in three equal parts.

\paper {
  line-width = 10\cm
  ragged-right = ##f
}

\new ChordGrid \with {
  \override ChordSquare.measure-division-lines-alist =
    #'(((1) . ())
       ((1/3 1/3 1/3) . ((-1 -0.4 0 1) (0 -1 1 0.4))))
  \override ChordSquare.measure-division-chord-placement-alist =
    #'(((1) . ((0 . 0)))
       ((1/3 1/3 1/3) . ((-0.7 . 0.5) (0 . 0) (0.7 . -0.5))))
}
\chordmode {
  \time 3/4
  c2.
  c4 c4 c4
}

See also

Music Glossary: chord grid.

Internals Reference: ChordGrid, ChordGridScore, GridChordName, ChordSquare, Grid_chord_name_engraver, Chord_square_engraver.