Sophisticated Arp Generator from your chosen chord progressions | Download the MIDI for free to use inside your own DAW.


Create musical arpeggios from your own chord progressions with our Polyrhythm Arp MIDI Generator. Choose from classic up, down and octave patterns, or explore more complex rhythms using cross-rhythms, polyrhythms and polymetric sequences that move across the bar line and create evolving rhythmic movement.

Shape the arp with different note patterns, octave movement, rhythmic layers and harmonic settings, then audition the result with your chords before exporting it as a MIDI file for your DAW. The generator can create anything from simple repeating arpeggios to longer, shifting patterns where different rhythmic cycles interact and gradually realign.

Create musical arpeggios from a chord progression. The engine can create classic up/down arps, deliberate octave-bouncing patterns, note-order and accent cycles across chord boundaries, genuine cross-rhythms and Euclidean patterns, then add an optional independent rhythmic layer for polyrhythmic top notes, roots, octave pulses or polymetric cycles. It auditions multiple complete phrases and keeps the most musical result.
Suggested key: This progression fits A Natural Minor / C Major / G Mixolydian.
Enter chords separated by dashes, commas or arrows. Example: Am - F - C - G. Slash chords are supported. Each chord = one bar.
MAIN ARP only. Inactive unless Rhythm is Cross Rhythm or Evolving Cycle; Secondary Layer Cycle works independently below.
3
SpaceBusy
Shapes register separately from the Note Pattern. Natural keeps the original arp behaviour.
70%
10%
5ms
10
Across Chords lets rhythmic and note cycles interlock with chord changes.
Adds an independent secondary pulse without changing the main arp.
SECONDARY VOICE: inactive while Rhythmic Layer is Off.
Play With Arp adds the layer note independently. Replace removes the nearest main arp note and puts the layer note at its own polyrhythmic or polymetric timing.
Subtle sits behind the arp; Clear makes the secondary rhythm easier to hear.
A3 – E4 – C4 – E4 – E4 – C4 – C4 – A3 – F3 – C4 – F4 – F4 – A4 – C5 – C5 – F5 – G5 – C5 – G4 – C5 – C5 – G4 – G4 – C5 …
Am → F → C → G
Am
F
C
G
A
E
C
E
E
C
C
A
F
C
F
F
A
C
C
F
G
C
G
C
C
G
G
C
G
B
G
D
D
G
D
G
Am
Motif
A3 – E4 – C4 – E4 – E4 – C4 – C4 – A3
8 notes · beats 0 · 0.50 · 1 · 1.50 · 2 · 2.50 · 3 · 3.50
F
Repeat
F3 – C4 – F4 – F4 – A4 – C5 – C5 – F5
8 notes · beats 0 · 0.50 · 1 · 1.50 · 2 · 2.50 · 3 · 3.50
C
Variation
G5 – C5 – G4 – C5 – C5 – G4 – G4 – C5
8 notes · beats 0 · 0.50 · 1 · 1.50 · 2 · 2.50 · 3 · 3.50
G
Resolution
G4 – B4 – G4 – D4 – D4 – G4 – D4 – G4
8 notes · beats 0 · 0.50 · 1 · 1.50 · 2 · 2.50 · 3 · 3.50
Musical Sequence · Natural · 2 octavesNote + octave pattern
StraightRhythm
Across chordsPattern flow
OffRhythmic layer
Musical Sequence · Natural · Subtle evolutionNatural octave movement keeps the original note-order behaviour. The note-order cycle continues through chord changes, so harmony can change underneath an unfinished pattern instead of every bar sounding restarted. Candidate selection rejects collisions, over-busy patterns, excessive gaps and pitch sequences that become stuck or needlessly jumpy.
Need a chord progression first?

Use our Chord Progression Generator to create more advanced chord progressions, then simply copy the chords and paste them into the Polyrhythm Arp MIDI Generator above.

How to Use the Polyrhythm Arp MIDI Generator

Start by entering a chord progression such as Am – F – C – G, then choose the note pattern, rhythm and octave movement for your arp. You can create straightforward up/down arpeggios or introduce cross-rhythms, evolving patterns and secondary rhythmic layers.

Press Generate Arp to create a new pattern, audition it with the chord progression and adjust the controls until you find something you like. When you are finished, download the pattern as a MIDI file and drag it directly into your DAW.


Create Polyrhythmic Arpeggios

Unlike a conventional arpeggiator, this generator can run different rhythmic ideas at the same time. The main arp can remain on a straight rhythm while a root, octave or highest chord note follows a separate 3:2, 3:4 or 5:4 polyrhythm.

The additional rhythmic note can either play alongside the main arp or replace a nearby arp note. This allows the secondary rhythm to become part of the musical pattern rather than simply adding more notes on top.


Create Evolving Polymetric Arp Patterns

Polymetric patterns use repeating cycles that are a different length from the underlying 4/4 bar. A 5-step or 7-step sequence therefore begins at a different position within each bar before eventually returning to its original alignment.

Use Complete Cycle to generate the full sequence required for the chord progression and polymetric pattern to return to their original starting relationship. This can create long, evolving MIDI sequences while the underlying musical idea remains simple and recognisable.


Classic Arpeggios and Octave Patterns

You do not have to use polyrhythms or polymeter. The generator can also create traditional up, down and up/down arpeggios, octave-bouncing patterns, rising and falling sequences and wider melodic arp movements.

This makes it useful for everything from simple synth arpeggios and house sequences to more complex electronic, ambient and experimental rhythmic patterns.


Download Your Arpeggio as MIDI

Every generated pattern can be exported as MIDI and opened in your DAW, where you can change the sound, timing, velocity or individual notes. When a secondary rhythmic layer is used, it can remain separate from the main arp so the two parts can be edited independently or assigned to different instruments.


Build a Complete Musical Idea

Use the same chord progression with our Melody Generator and Bassline Generator, then build a rhythm around the idea using the Drum & Percussion Generator.

If you want to explore rhythmic relationships in more detail, try the Polyrhythm Generator, or visit our MIDI Generators page to explore all of our free music production generators.