6 ms·

A Generative Grammar for Jazz Chord Sequences (1984)

100 points by wcerfgba 6y ago

Y_Y 6y ago
Has anyone ever put this into code?
- prionassembly 6y ago
  The software "Band-in-a-box" used to have a passable jazz solo generator. Probably still does.
- thetanil 6y ago
  Many have. This is more or less how I learn every new programming language. Generative music is really fun and immediate. Anyway, I think the first time I ever saw anyone introduce recursion into music generation was Giles Bowkett's Archaeopteryx. That was way back in the days when Ruby was still young and cool. He did some interesting stuff for keeping a stable clock in ruby using recursion without blowing up the stack, but also managed to use the same technique for generating variations on probabilistic sequences. Pick your language and you will find people doing small projects like this all over the place.
alkonaut 6y ago
What's the relation in chord progressions between Jazz and Blues? I only read the article quickly so it might be mentioned, but it's odd that the title says "Jazz" and mostly deals with the progressions known as "12 bar blues". A straight 12-bar blues progression would be recognized as "blues" by any listener, so presumably there is something that makes such a progression sound more like jazz than blues. But what is it? Is it through the number of tweaks added, such as more "jazzy" chords like 9/11/13 chords? Is there something else that distinguishes jazz from blues in a 12 bar progression? Edit: I found an explanation here: https://music.stackexchange.com/questions/71149/how-can-you-recognize-whether-a-song-is-blues-or-jazz https://music.stackexchange.com/questions/71149/how-can-you-...
- tgv 6y ago
  I think the article focuses on the 12 chord blues progression to show how the rules can turn I-IV-I-V into something which could be considered jazz, by introducing sevenths and substitutions. And since it's a generative grammar, it also needs a starting point...
- prionassembly 6y ago
  Short answer to the narrower question: a "jazz blues" song like Parker's "Blues for alice" has a turnaround. https://en.wikipedia.org/wiki/Turnaround_(music) https://en.wikipedia.org/wiki/Turnaround_(music) OTOH straight delta/Chicago blues can compress the whole I/IV/V language in a single bar, as in Muddy Waters' "Mannish boy".
- kleinsch 6y ago
  Blues is both a style of music as well as the name of a chord progression (that’s used in that style of music). You could play that chord progression in a Latin or bebop style and you’d be playing a 12-bar blues, but you wouldn’t be playing the Blues.
  - WorldMaker 6y ago
    A fun example: NRBQ has a (classic) song called "12-Bar Blues" with lyrics about playing a "12-bar blues" and demonstrates a 12-bar blues progression inside it but whose tone/style is much farther toward R&B/Rock than the Blues.
- aczerepinski 6y ago
  The chords don’t need to be different. A jazz blues would also (usually) be characterized by a walking bass and lack of a backbeat on the drums. Thelonious Monk’s “Blue Monk” is an example with pretty standard blues changes. That being said, there are infinite variations of blues chord progressions in the jazz canon. Some great examples are Charles Mingus’s “Goodbye Pork Pie Hat,” and “Nostalgia in Times Square.” Then you have examples that are closer to standard blues but with a few substitutions, like Joe Henderson’s “Isotope.”
- tunesmith 6y ago
jncraton 6y ago
If you're interested in this sort of grammar application, I created a project a while back that uses a generative grammar to connect LEGO bricks into models: https://github.com/jncraton/connectiongrammar https://github.com/jncraton/connectiongrammar
- bloudermilk 6y ago
  This is some fantastic work. Thank you for sharing!
solinent 6y ago
I'm a jazz musician--it's interesting stuff, there is a whole area of research dedicated to this type of work. Jazz chord progressions are pretty simple ultimately when expressed in compressed form, but tend to have actual semantics behind them be pretty communicative so I doubt this will cover absolutely everything except the popular works. You can generate something very close using a formal grammar but you get stuck in the same position as the logicians in Chomsky's time. I've had some really great thoughts about ML approaches, however, with some sort of seq-to-seq approach.
- AndrewUnmuted 6y ago
  > I've had some really great thoughts about ML approaches So far I've had the most luck doing a Peephole LSTM approach [0]. [0] https://en.wikipedia.org/wiki/Long_short-term_memory https://en.wikipedia.org/wiki/Long_short-term_memory
  - Rochus 6y ago
    Here, too, the development is moving away from RNN and LSTM in the direction of Transformers. One of the most promising algorithmic composition projects I recently came across is https://openai.com/blog/musenet/ https://openai.com/blog/musenet/.
- Rochus 6y ago
  There are many ideas, even books full of ideas (see e.g. https://www.amazon.com/Algorithmic-Composition-Paradigms-Automated-Generation/dp/3211999159 https://www.amazon.com/Algorithmic-Composition-Paradigms-Aut...), but I rarely hear an example which is not disappointing. Recent developments seem to produce better results. If you're interested in a current approach with very promising results see e.g. https://openai.com/blog/musenet/ https://openai.com/blog/musenet/.
tonystride 6y ago
This makes me think of the way that an experienced jazz musician can seemingly know an overwhelming amount of standards (common practice jazz songs). Or how jazz musicians are expected to pick up a tune on the spot even if they don't know it. The key to this seems to be that most jazz progressions are based on circle of fifths, or interlocking cells of CoF progressions. This would imply that there is a grammar of jazz chord sequences that experienced musicians use to play or fake a massive amount of repertoire without having to cram rote learning every day.
- merolish 6y ago
  Jazz guitarist here, and yes. One of the nice things about the instrument is that a relatively small number of forms for chords and scales are transposable up and down the fretboard, so once you burn the usual patterns into your head (iim7-V7-IM7, etc.) reading a new sheet usually doesn't take too much work. Most pop music is even simpler, as illustrated by Axis of Awesome. https://www.youtube.com/watch?v=5pidokakU4I https://www.youtube.com/watch?v=5pidokakU4I
  - boston_clone 6y ago
    Have you explored Barry Harris and his diminished sixth approach to jazz? I'm still clawing through it, but it seems to simplify the amount of chords you play to only 2 and then defines what variations will consistently sound good.
    - tonystride 6y ago
      Never done a deep dive on BH but I'm very aware of him. It's funny how theory can seek to reduce down so much, the positive and the negative. Kinda like Shankerian, except I would be much more interested in what BH has to say since Shanker was such an terrible person.
      - seanhunter 6y ago
        I think you're talking about "Schenkerian" analysis, right? https://en.wikipedia.org/wiki/Schenkerian_analysis https://en.wikipedia.org/wiki/Schenkerian_analysis
deleted 6y ago
[deleted]
stevehiehn 6y ago
Interesting, My holiday code project happened to be generating chord progressions with graph theory and it worked very well (imo) check it out: http://signalsandsorcery.com http://signalsandsorcery.com
- stevehiehn 6y ago
  ps - source code: https://github.com/shiehn/SignalsAndSorcery https://github.com/shiehn/SignalsAndSorcery (Tone.js + SpringBoot)
aifer4 6y ago
I wonder if anyone’s written a parser for this and applied it to a large number of songs. I would be curious to see how often each rule is used. On a related note, I would be interested to know whether the grammar is ambiguous.

100 points by wcerfgba 6y ago

Y_Y 6y ago

Has anyone ever put this into code?

prionassembly 6y ago
The software "Band-in-a-box" used to have a passable jazz solo generator. Probably still does.
thetanil 6y ago
Many have. This is more or less how I learn every new programming language. Generative music is really fun and immediate. Anyway, I think the first time I ever saw anyone introduce recursion into music generation was Giles Bowkett's Archaeopteryx. That was way back in the days when Ruby was still young and cool. He did some interesting stuff for keeping a stable clock in ruby using recursion without blowing up the stack, but also managed to use the same technique for generating variations on probabilistic sequences. Pick your language and you will find people doing small projects like this all over the place.

alkonaut 6y ago

What's the relation in chord progressions between Jazz and Blues? I only read the article quickly so it might be mentioned, but it's odd that the title says "Jazz" and mostly deals with the progressions known as "12 bar blues". A straight 12-bar blues progression would be recognized as "blues" by any listener, so presumably there is something that makes such a progression sound more like jazz than blues. But what is it? Is it through the number of tweaks added, such as more "jazzy" chords like 9/11/13 chords? Is there something else that distinguishes jazz from blues in a 12 bar progression? Edit: I found an explanation here: https://music.stackexchange.com/questions/71149/how-can-you-recognize-whether-a-song-is-blues-or-jazz https://music.stackexchange.com/questions/71149/how-can-you-...

tgv 6y ago
I think the article focuses on the 12 chord blues progression to show how the rules can turn I-IV-I-V into something which could be considered jazz, by introducing sevenths and substitutions. And since it's a generative grammar, it also needs a starting point...
prionassembly 6y ago
Short answer to the narrower question: a "jazz blues" song like Parker's "Blues for alice" has a turnaround. https://en.wikipedia.org/wiki/Turnaround_(music) https://en.wikipedia.org/wiki/Turnaround_(music) OTOH straight delta/Chicago blues can compress the whole I/IV/V language in a single bar, as in Muddy Waters' "Mannish boy".
kleinsch 6y ago
Blues is both a style of music as well as the name of a chord progression (that’s used in that style of music). You could play that chord progression in a Latin or bebop style and you’d be playing a 12-bar blues, but you wouldn’t be playing the Blues.
- WorldMaker 6y ago
  A fun example: NRBQ has a (classic) song called "12-Bar Blues" with lyrics about playing a "12-bar blues" and demonstrates a 12-bar blues progression inside it but whose tone/style is much farther toward R&B/Rock than the Blues.
aczerepinski 6y ago
The chords don’t need to be different. A jazz blues would also (usually) be characterized by a walking bass and lack of a backbeat on the drums. Thelonious Monk’s “Blue Monk” is an example with pretty standard blues changes. That being said, there are infinite variations of blues chord progressions in the jazz canon. Some great examples are Charles Mingus’s “Goodbye Pork Pie Hat,” and “Nostalgia in Times Square.” Then you have examples that are closer to standard blues but with a few substitutions, like Joe Henderson’s “Isotope.”
tunesmith 6y ago

jncraton 6y ago

If you're interested in this sort of grammar application, I created a project a while back that uses a generative grammar to connect LEGO bricks into models: https://github.com/jncraton/connectiongrammar https://github.com/jncraton/connectiongrammar

bloudermilk 6y ago
This is some fantastic work. Thank you for sharing!

solinent 6y ago

I'm a jazz musician--it's interesting stuff, there is a whole area of research dedicated to this type of work. Jazz chord progressions are pretty simple ultimately when expressed in compressed form, but tend to have actual semantics behind them be pretty communicative so I doubt this will cover absolutely everything except the popular works. You can generate something very close using a formal grammar but you get stuck in the same position as the logicians in Chomsky's time. I've had some really great thoughts about ML approaches, however, with some sort of seq-to-seq approach.

AndrewUnmuted 6y ago
> I've had some really great thoughts about ML approaches So far I've had the most luck doing a Peephole LSTM approach [0]. [0] https://en.wikipedia.org/wiki/Long_short-term_memory https://en.wikipedia.org/wiki/Long_short-term_memory
- Rochus 6y ago
  Here, too, the development is moving away from RNN and LSTM in the direction of Transformers. One of the most promising algorithmic composition projects I recently came across is https://openai.com/blog/musenet/ https://openai.com/blog/musenet/.
Rochus 6y ago
There are many ideas, even books full of ideas (see e.g. https://www.amazon.com/Algorithmic-Composition-Paradigms-Automated-Generation/dp/3211999159 https://www.amazon.com/Algorithmic-Composition-Paradigms-Aut...), but I rarely hear an example which is not disappointing. Recent developments seem to produce better results. If you're interested in a current approach with very promising results see e.g. https://openai.com/blog/musenet/ https://openai.com/blog/musenet/.

tonystride 6y ago

This makes me think of the way that an experienced jazz musician can seemingly know an overwhelming amount of standards (common practice jazz songs). Or how jazz musicians are expected to pick up a tune on the spot even if they don't know it. The key to this seems to be that most jazz progressions are based on circle of fifths, or interlocking cells of CoF progressions. This would imply that there is a grammar of jazz chord sequences that experienced musicians use to play or fake a massive amount of repertoire without having to cram rote learning every day.

merolish 6y ago
Jazz guitarist here, and yes. One of the nice things about the instrument is that a relatively small number of forms for chords and scales are transposable up and down the fretboard, so once you burn the usual patterns into your head (iim7-V7-IM7, etc.) reading a new sheet usually doesn't take too much work. Most pop music is even simpler, as illustrated by Axis of Awesome. https://www.youtube.com/watch?v=5pidokakU4I https://www.youtube.com/watch?v=5pidokakU4I
- boston_clone 6y ago
  Have you explored Barry Harris and his diminished sixth approach to jazz? I'm still clawing through it, but it seems to simplify the amount of chords you play to only 2 and then defines what variations will consistently sound good.
  - tonystride 6y ago
    Never done a deep dive on BH but I'm very aware of him. It's funny how theory can seek to reduce down so much, the positive and the negative. Kinda like Shankerian, except I would be much more interested in what BH has to say since Shanker was such an terrible person.
    - seanhunter 6y ago
      I think you're talking about "Schenkerian" analysis, right? https://en.wikipedia.org/wiki/Schenkerian_analysis https://en.wikipedia.org/wiki/Schenkerian_analysis

deleted 6y ago

[deleted]

stevehiehn 6y ago

Interesting, My holiday code project happened to be generating chord progressions with graph theory and it worked very well (imo) check it out: http://signalsandsorcery.com http://signalsandsorcery.com

stevehiehn 6y ago
ps - source code: https://github.com/shiehn/SignalsAndSorcery https://github.com/shiehn/SignalsAndSorcery (Tone.js + SpringBoot)

aifer4 6y ago

I wonder if anyone’s written a parser for this and applied it to a large number of songs. I would be curious to see how often each rule is used. On a related note, I would be interested to know whether the grammar is ambiguous.