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Bass to Chords

Select your bass line and get a chord track that fits it.

Jazzy, rhythmic or arpeggiated. Works 100% offline.

Get it · $10 How it works Try it free

Ableton Live 12 extension · macOS

A bass line turning into chords, as cut paper A piano roll made of cut-paper strips. Orange bass notes walk D, G, C along the bottom. Above them sit three rootless chord voicings, Dm9 in blue, G13 in green and Cmaj9 in yellow, one per bar. Dm9 G13 Cmaj9
A walking bass in, rootless chords out.

How it works

  1. 1Select your bass line in Arrangement View.
  2. 2Right-click → Chords from Bass…
  3. 3Hit Create.
  4. 4It reads the key and time signature, works out where the chords change, and writes a chord clip on a new MIDI track with an instrument already loaded.
The panel inside Live, one right-click away.

Every control, one panel

Your key, your call.

With Scale Mode on, it uses your Set's key. Otherwise it detects the key from the bass. Either way you can pick any key yourself.

Chord changes
A new chord where the bass moves to a new root. Passing notes and arpeggios keep the chord they belong to. Or change on every note, every bar, every 2 bars or every 2 beats.
Styles
Jazzy: held chords that push when your bass pushes, with an optional strum. Rhythmic: your bass rhythm, or Charleston, offbeats, funk 16ths, syncopated comping. Arpeggiated: 1/8, 1/16 or triplets, up, down or up-down, over one or two octaves.
Complexity
Triads, 7ths or 9ths / 11ths / 13ths, in a low, mid or high register, plus swing and humanize.
Time signatures
4/4, 3/4, 6/8 and 6/4, detected from the bass or set by hand.

Three takes on every line

A Original

The chords the bass implies, with classic voicings. Same result every time.

B Revoiced

The same chords with new jazz voicings: drop 2, drop 3, spreads, 4ths, upper structures. Different every run.

C Reharm

Reharmonized with richer colours, sus chords and approach chords. Different every run.

What you get

Voicings that sit right

Rootless, since your bass already has the root. Low voicings open up so they don't turn to mud, and each chord moves smoothly into the next.

Labelled for you

The clip is named with the progression, like Dm9 | G13 | Cmaj9, and the track with the key, style and take.

Nothing gets touched

It only adds a new track. Your bass line is never changed, and everything can be undone.

What it's not

Not a progression generator that ignores what you played. It reads your bass line and harmonizes it. It needs a MIDI bass line, not audio.

Specs

Host
Ableton Live 12 with Extensions support (Extensions are currently in beta)
Platform
macOS, built and tested on Mac
Input
A MIDI bass line in Arrangement View
Install
Drop the .ablx onto Live's Settings → Extensions page. It appears when you right-click an Arrangement selection on a MIDI track.
Privacy
100% offline, ever. No tracking, no analytics, no account, no license check.
Price
$10

Bass to Chords is an independent tool and isn't affiliated with or endorsed by Ableton.

Bass to Chords

Stuck with just a bass line?

Get it · $10 Found a bug? Write me

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