Re: Lilypond and Jazz chords

[Carl D. Sorensen]

On 6/2/09 3:55 AM, "Jean-Alexis Montignies" <address@hidden> wrote:

> Hi there, as a jazz player I would like to share my input.

Thanks for sharing, Jean-Alexis.

> 
> What I need in scores is really chord names.
> The chord name denotes the intent of the composer and is much subject
> to interpretation.
> 
> Some examples:
> If you have a dominant chord, you write G7. Most of the time, the
> pianist will not play the 5th and depending on the context will play a
> 9th or a flattened 9th.
> If you write G7b9, it just means that if you play a 9th, you should
> play a flattened one (probably the melody have a flattened 9th).
> In the real book, most 7b5 chords should really be written 7#11, but
> this is another story.
> I found a score where a chord was named 'phrygian'.
> 
> The problem I ran when i wrote chords in Lilypond:
> 
> 1) I had some difficulties to write the Alt chords (for me it's based
> on the superlocrian scale 1 2- 2+ 3 4+ 6- (or 5+) 7-)  because the
> scale has two seconds. (Note that the diminished scale cannot be
> written for now with the chord notation, if you ever want to write a 8
> note chord ;) ).

This an issue in chord input mode, and should be reported to bug-lilypond as
an enhancement request.  For you, the limitation of only one instance of
each step in a chord is a limitation.

> 2) There no way to write N.C. : no chord (wouldn't the use of R, r and
> s make sense in the chord mode?)

N.C. is implemented for r in chordNames context starting with 2.13.1.  It
will be available in the next development version.  Support for generating
N.C. with R is planned.  I don't think that s should generate N.C.; s means
don't output anything.

> 3) I had to use some tricks for chords that last on several measures
> for the symbol not to repeat on each measure.

\set ChordChanges = ##t is all that it takes.

> 4) I would have liked to use parenthesis around the column for chord
> extensions like in most jazz charts. I used brackets instead.

I hope we'll be able to implement this, but if we don't, remind us again.

> 
> Lilypond of other programs will never be able to interpret notes as
> chords (even humans can't do that because there are always ambiguities).
> 
> I think the more sensitive approach for pop and jazz is a chord
> library with a string as input (maj7) and as output a notation as
> markup for chord symbol, optionally as a realisation as notes or chord
> diagram (could even have options to select or override the realisation).

That's what we have in essence with our current chordmode.  The string has
some specific syntax, and it provides realization as notes, chord diagrams,
and chord names.  But the chord names functionality isn't what we want right
now.

> 
> I myself need only the chord symbol. Such a simple model is in my
> opinion simple to use, customizable and extends easily to other
> musics. For me the chord name is more semantics than just notes.
> 
> You'll find my current chord exception list below, note that i've used
> the unicode chars for the flat and sharp before the extensions as it
> gives a very natural layout in this case.

Thank you for this exception list.  It provides a nice reference.

The major problem with an exception list is that it doesn't handle slash
chords; I hope to be able fix that.


Thanks,

Carl