Chord Leadsheet

Use the chord leadsheet editor to:

  • Add chord symbols, eg “Cm6”, “Ab7”
  • Add sections, eg “A”, “B”, “verse”, “chorus”, …
  • Move and edit chords to adjust rhythm accents, interpretation or harmony

Chord leadsheet editor image

Chord symbols


Select a bar or a chord symbol then:

  • type the first letter of the chord symbol (‘A’ to ‘G’), or
  • press ENTER, or
  • double-click, or
  • right-click menu, Edit

You can also select an existing chord symbol and move it while pressing the ctrl button, it will create a new copy that can be edited.

To move a chord symbol just select it and move it with the mouse.

To input a complete leadsheet the easier way is to select the first bar, directly type in the chord symbols, press ENTER (it will automatically select the next bar), type in the chord symbols for the second bar, etc.

To change the size of the leadsheet, select a bar then right-click menu and select Set End Bar.

Use ctrl-click or shift-click for multiple selection.


JJazzLab recognizes many aliases for each chord symbol. For example C7M can be written Cmaj7 or Cma7 etc.

If required you can add more aliases using the menu Tools/Options/Chord Symbols panel.


Select a chord symbol, edit it and select the Interpretation tab.

Chord symbol interpretation image

The Interpretation tab lets you decide how this chord symbol should be played:

  • Normal
  • Accent: add a rhyhtmic accent
  • Hold: add a rhythmic accent and hold notes until next chord symbol
  • Shot: add a rhythmic accent with chord notes played briefly

Note: each rhythm generation engine may use these Interpretation parameters differently, some may even ignore them. For example the YamJJazz rhythm engine uses the Interpretation parameters to modify the drums, bass, piano/guitar and pad tracks.

The shape of the marker below the chord symbol depends on the interpretation mode:

interpretation markers image

For example, in order to render: Chord symbol interpretation image

you could use the following interpretation parameters: Chord symbol interpretation image Hint: use the P shortcut from the chord leadsheet editor to directly change the interpretation of the selected chord symbols .

Chord anticipation

When you move a chord symbol to an off-beat position (for example the F#7 above), the YamJJazz engine will render it as an anticipated chord, unless you uncheck the checkbox “Enable chord anticipation” in the Interpretation tab.


Select a chord symbol, edit it and select the Harmony tab.

Chord symbol harmony image

The Harmony tab lets you select the scale to be used when rendering the music for this chord symbol.

Example: Suppose that the reference bass line for Eb7M contains a Ab (4th degree of the Eb major scale). If you select the lydian mode (which has a sharp 11th degree) then the reference bass note Ab will be rendered as A for this chord symbol.

By default no scale is selected: each rhythm generation engine will decide the “best” scale to use.

Note: some rhythm generation engines may ignore harmony parameters.

Alternate chord symbol

Select a chord symbol, edit it and select the Alternate chord symbol tab.

Chord symbol alternate image

This tab lets you define an alternate chord symbol which will be used when some conditions are met. The alternate chord symbol can be a completly different chord symbol, the same but with a different interpretation or harmony, or no chord symbol at all (void chord). This is useful when you need to introduce a slight variation during a song.

Chord symbols which have an alternate chord symbol defined are displayed with a different color (see image below).


In the Carlos Santana’s “Europa” song, the 1st ending of the theme is a Cm7, but the 2nd one is a C major. To implement this in JJazzLab, one solution could be to duplicate section A1 to create section A2 with the different ending, then update the song structure accordingly. This is perfectly fine, but when changes are minor the alternate chord symbol can provide a simpler solution.

You can see below (and in the dialog snapshot above) that a C7M alternate chord has been created for Cm7. C7M will be used for all song parts (see the Song Structure Editor) where the marker is set to Theme2. On the image below it means the C7M will be used on the 2nd occurence of section A1.

Chord symbol alternate image

There is another alternate chord symbol example in the 3rd bar: A7. If you listen to the original song you’ll notice that they play a A7 on the last beat of the 3rd bar only during solos. So the A7 chord symbol defines its alternate chord symbol as the “void chord symbol” (same as no chord symbol) when marker is not “Solo”.

Sections input

Typical sections are ‘intro’, ‘verse’, ‘chorus’, etc.

A Song section is the basic unit used by JJazzLab to define the song structure (see the Song Structure Editor). There is always a section defined on the first bar.

To add a section select a bar which is not after the end then:

  • press ENTER, or
  • double-click, or
  • right-click menu, Edit

The new section name must be different than the existing one.

Force a section at new line

You can force a section which is not on the first bar of a row to start on the next line. This can be useful when some sections have an odd number of bars.

Select a bar with a section defined or select the section itself, right-click menu “Force Section at New Line”.

Force section at new line 1 image
This will result in the display below. Force section at new line 2 image

Mouse shortcuts

Selection Mouse Action
Bar, Chord Symbol, Section        simple-click        select
Chord Symbol        double-click        edit using the chord symbol editor dialog
Bar, Section        double -click        edit using the bar editor dialog
Bar, Chord Symbol, Section        right-click        open the popup menu
Chord Symbol mouse wheel transpose chord symbol
Chord Symbol shift mouse wheel        change chord type
Editor ctrl mouse wheel change the X zoom factor

Keyboard shortcuts

Selection key Action
Chord Symbol        enter        edit using the chord symbol editor dialog
Bar, Section        enter        edit using the bar editor dialog
Bar        ctrl-E        set end bar
Bar        I        insert bars
Bar        delete        clear bar contents
Chord Symbol, Section        delete        remove
Bar        shift-delete        remove
Chord Symbol ctrl-up/down transpose
Chord Symbol P change interpretation
Chord Symbol, Section ctrl-A select similar items from the current section. Then from the chord leadsheet.
Bar, Chord Symbol, Section        ctrl-C/X/V copy/cut/paste items
Editor        ctrl-Z/Y        undo/redo
Editor        ctrl-O        set current song active (On/Off)
Editor        ctrl-W        close current song