Re: Chord Name Fixes

[Rune Zedeler]

address@hidden wrote:
> I said I'd do my best to fix the chords in lilypond a while ago, but
> personal commitments (and the daunting prospects of having to learn guile
> and LaTex) prevented me from getting around to it. However, I now have some
> time on my hands, and a burning desire to produce beuatiful jazz charts on
> lily.

Very very great!!! :-)

> First things first: fix input chord to pitch generation.

Sounds sensible.

> I'm currently holding fixes for chord generation. (e.g. "c:m13.5-", &c)
> which generates correct notes for pretty much anything I can think of
> throwing at it. The old code really didn't deal with anything above a 9th
> very well, and had all kinds of quirky behaviour.

I don't really understand what you mean here...

> Fix summary:
>     Enter chord names relatively intuitively. Any intuitive sequence of
> modifiers and alterations
>     produces the exepected result.

One thing I've learned during this is:
Don't assume ANYTHING about what is "expected".

>     No strange things with 4ths any more. Must use "sus" to remove the 3rd.

Hmmm, I hadn't though about it like that...
If it works then it is ok, I guess.
But I am not at all sure that it WOULD work in all cases... I am more a 
fan of the more hacky solution to make c:sus4 give <c eis g> and c:sus2 
give <c eses g>.
This would not be theoretically correct but it would be easy to backtrack.

>     11ths fixed up to produce 11+ for major, 11 for minor chords.

Eh??? I have NEVER heard about this and this would DEFINITELY NOT be 
what I would expect. I have learned about chord notation in 4 different 
schools, and in all of them we learned that the chord systems are based 
on the mixolydian scale.
How do you notate a Gm7/c if you cannot use Csus11 ???

>     Subtractions now affect only implicitly added notes, and ignore
> alterations.
>     (e.g.   maj13^7  removes the 7th m9^7 removes the 9th.) maj13^13 does
> not remove the 13).

I don't understand why m9^7 removes the 9th. Is m9^7 the same thing as 
m7? (Or did you make a typo?)



>     Multiple alterations of the same degree are permitted and work as
> expected.

I wouldn't know what to expect. Sounds more than strange to me.

>     e.g. alt chords of the form c:5+.5-  c:9+.9- &c.

last example giving <c e g bes des dis> ?

> By default, 11ths are augmented (whether added explicitly or implicitly).
> c:11 produces c e g bf d fs. A natural 11th may be added by specifying
> c:11-.

What about c:13 ? You also modify the 11th here?

> Chord modifiers affect the way implicit notes are added to the chord.
>
> m, min  :    implicit 3rds are minor. 11ths are natural.
> maj :         7ths are major (whether implicit or explicit).
> dim:          implicit 3rds are minor, implicit 5ths are diminished, 7ths
> are diminished.
> aug:           implicit 5ths are augmented.
> sus:           do not generate an implicit 3rd.

sound ok. Perhaps we also need hdim


> add:   adds the following note, but not implicit 3rds below it.

Not implicit anything below it, hopefully? c:add11 doesn't add the 9th, 
right?


> Modifiers do not add notes, but affect steps that are added afterward.
>
> Examples:
>         c:2    -->  c d e g
>         c:add9  -> c e g  d  (experimental)
>         c:sus2 --> c d g
>         c:maj13   -> c e g b d fs a

Oh. So you answerede my previous question here...
How would you notate a "real" c13? c:13.11- ?


-Rune