arp (arpeggiate)

Scribbletune can generate arpeggios from chords.

You can set the order of the notes in the arpeggiator and the count of notes in it.

const scribble = require('scribbletune');
 
const c = scribble.clip({
  notes: scribble.arp('CM FM CM GM'),
  pattern: 'x'.repeat(32)
});
 
scribble.midi(c, 'arp.mid');

This will create a MIDI clip with the notes of the chord progression in an arpeggiated format where each note is a quarter note. You can change this by setting a property called subdiv.

subdiv: '16n'

Now it plays a bit faster as we set the default duration of each note to sixteenth notes. By default, the arp method uses 4 notes per arpeggio and it plays those notes from 0 to 3. But you can change that, as the arp method also accepts an object as its argument instead of a String.

const scribble = require('scribbletune');
 
  const notesArr = scribble.arp({
  chords: 'Cm Fm Cm Fm Cm Gm Cm DM',
  count: 3,
  order: '102'
});
 
const c = scribble.clip({
  notes: notesArr,
  pattern: 'x-x_'.repeat(notesArr.length/2),
  subdiv: '16n'
});
 
scribble.midi(c, 'arp.mid');

This will create a midi file called "arp.mid" at the same location as you run this script with `node` and it will arpeggiate the triads Cm, Fm, Cm, Fm, Cm, Gm, Cm and DM chords each with 3 notes in them ordered as 1 0 2. So if the first arpeggio (for Cm) was C4 D#4 G4 then the order of these notes would be 1 0 2, which is D#4 C4 G4

Here's how it sounded when I imported the MIDI file it produced into Ableton Live

You can use this in the browser as well. Just make sure to pull in Tone.js first however!