Chords returned by Scale.scaleChords

[colshacol]

I am confused as to how to work with this. I was expecting the output to be more along the lines of the actual chords in the scale, i.e: Cmaj, Dmin, Emin, Fmaj, Gmaj, Amin, Bdim, Cmaj7, etc...

Any advice on how I can get the data I am looking for?

[razznblue]

You need to use the 'key' module to get the data you are looking for.
For ES6 syntax:

import { Key } from "@tonaljs/tonal";

const keyChords = Key.majorKey("C");
###console.log(keyChords.chords);

Output:
["Cmaj7", "Dm7", "Em7", "Fmaj7", "G7", "Am7", "Bm7b5"]``

Documentation on the tonal-key package:
https://www.npmjs.com/package/tonal-key

Hope this helps! :)

[colshacol]

Ah, alright! I missed the Key package.

Key.majorKey(...).chords gives you just the 7th chords, though.

I noticed that the tonal-key package gives you the .triads method, so combining these two (or resorting to simply using tonal-key methods chords and triads) I can get a good set of chords from a scale, such as: ["C", "Dm", "Em", "F", "G", "Am", "Bdim", "CMaj7", "Dm7", "Em7", "FMaj7", "G7", "Am7", "Bm7b5"]

Any advice on how I should be applying the original output to these chords to get the full list of chords/variants that would fit in my key/scale? ["5", "64", "M", "M13", "M6", "M69", "M7add13", "M7sus4", "M9", "M9sus4", "Madd9", "Maj7", "Msus2", "Msus4", "sus24"]

[razznblue]

Yes good find about the triads in the tonal-key package! I also am a musician so I was confused too between the scale and key packages! 😂 I love music theory so this library is very interesting to me!

Also could you provide a specific example for what you are wanting to access in your last paragraph? It is the part where you mention about getting the full list of chords/variants in your key/scale.
Sorry, I just want to make sure I understand fully what you are asking so I can try to help! 😎

[colshacol]

I am currently running a puppeteer script to scrape the scale/chord associations from some outdated website. 😋 What I needed to get from tonal is, for example, is the following chords when I input "A major":

[ "C#m", "D", "E", "F#m", "G#dim", "A", "Bm", "C#sus4", "Dsus2", "Esus4", "Esus2", "F#sus4", "F#sus2", "Asus4", "Asus2", "Bsus4", "Bsus2", "C#m7", "C#7sus4", "D6", "Dmaj7", "E6", "E7", "E7sus4", "E7sus2", "F#m7", "F#7sus4", "F#7sus2", "G#m7b5", "A6", "Amaj7", "Bm6", "Bm7", "B7sus4", "B7sus2", "C#m11", "D6/9", "Dmaj9", "Dmaj13", "E6/9", "E9", "E13", "E9sus4", "E9sus2", "F#m9", "F#m11", "F#9sus4", "F#9sus2", "A6/9", "Amaj9", "Amaj13", "Bm9", "Bm11", "Bm13", "B9sus4", "B9sus2" ]

Basically, I need to be able to access every chord and variation that fits in a key/scale.

[colshacol]

Here is the data I scraped. The source seemed pretty trustworthy, albeit outdated. 🤷‍♂️

[razznblue]

Ok I see what you need. I am not too sure at the moment how to do that but I will research it more and hopefully we can find a good solution!

[colshacol]

Since you seem to know a little more about music theory than I do, let me you ask you this:

If, for example, C major contains the notes C, D, E, F, G, A, and B, would any chord I composed out of these notes fit in the scale?

[razznblue]

Yes, that is correct. As long as all of the notes in a given chord fit into a scale, then the chord fits in that scale.

[danigb]

Hello!

I think you are mixing several things here.

Each key naturally have some chords. You can find them using the Key module 👉 https://github.com/tonaljs/tonal/tree/master/packages/key

1. Major key chords

The majorKey function returns an object with all chords (but under different keys). You have to merge them all. For example:

import { Key } from "@tonaljs/tonal";

const majorC = Key.majorKey('C')
const allChords =  [
  ...majorC.chords, 
  ...majorC.secondaryDominants, 
  ...majorC.secondaryDominantsMinorRelative, 
  ...majorC.substituteDominants, 
  ...majorC.substituteDominantsMinorRelative
].filter(x => x)
console.log(allChords)

Outputs:

[
  'Cmaj7', 'Dm7',  'Em7',   'Fmaj7',
  'G7',    'Am7',  'Bm7b5', 'A7',
  'B7',    'C7',   'D7',    'E7',
  'Em7b5', 'F#m7', 'Gm7',   'Am7',
  'Bm7b5', 'Eb7',  'F7',    'Gb7',
  'Ab7',   'Bb7',  'Em7',   'Cm7',
  'Dbm7',  'Am7',  'Fm7'
]

2. Major key scales

But also each Key has several scales (or modes). And lot of chords can "fit" an scale.

That's when scaleChords function comes in:

Scale.scaleChords('C major') // => 
[
  '5',      'sus4',
  'M7sus4', 'M',
  'maj7',   '6',
  'sus2',   'sus24',
  'M9sus4', 'Madd9',
  'maj9',   '6/9',
  'maj13',  'M7add13'
]

That result means that "C5", "Csus4", "CM7sus4", ... chords fits on C major scale.

You could apply the same operation to every scale on the key.

[jabza]

Regarding this, when trying scaleChords on C minor, I noticed 'M' is not returned, but C minor includes notes to form major chords, possibly am I misunderstanding this?

Scale.scaleChords('C minor') // => 
[
  '5',     '7#5sus4', 'sus4',
  '7sus4', 'm#5',     'm7#5',
  'm',     'm7',      '4',
  'madd4', 'm7add11', 'sus2',
  'sus24', '11',      '9sus4',
  'm9#5',  'madd9',   'm9',
  'm11A',  'm11'
]

Cheers

update

Using Scale.modeNames in conjunction Scale.scaleChords seems like the right way to go about what I wanted. It yields 'all' chord shapes that can exist, I then apply extra filtering depending on the tonic.