One Man Band 12 Also still available One Man Band Originals.
The easiest and most powerful auto-accompaniment software.
Virtual arranger keyboard and style editor for Windows and Macintosh.
Provides auto-accompaniment, both in realtime and sequenced.

One Man Band is the software version of the digital music instruments known as arranger keyboards, home keyboards and workstations. It creates auto-accompaniment based on the played chords and it adds auto-harmony to the played melody. Chords and melody can be played in realtime in the Live Window, with or without a connected MIDI keyboard controller or pre-entered in the Sequencer Window. It utilises standard style files compatible with the styles used in Yamaha PSR, DGX and Tyros arranger keyboards. There are thousands of these styles available on internet and the included style editor can be used to tweak existing and create new styles.

What's new in version 12?

Playing Live
Control operations thru the computer keyboard, a (second) MIDI keyboard controller or a touch screen. Design your own menus with on screen actions. Use an Android device as touchscreen with the JmRemote app, available in the Google Play Store.


Sequencing / Arranging
6 different views on the same MIDI file: Main/Recorder, Arranger, Pianoroll, Karaoke, Eventlist and Staff.


Both Live and Sequenced Auto-harmony will be added based on defined Multivoices.


Editing Styles
Style editor and MIDI file to Style converter.


Download Demo: Windows / Mac OS 64 bit / Mac OS 32 bit for old computers
Fix for Mac OS 10.15 Catalina
Fix for problem in Windows 7
Buy Now:
Windows /Mac OS (you get both the 64 and 32 bit versions for the Mac)
Upgrade from OMB Originals or V11
Free Styles
More Software


How to install One Man Band
Live: Playing chords and melody
Live: Choosing an interface
Live: Customising the interface
Live: Assigning MIDI to actions
Live: Recording
Sequencer: Create a song without playing
Sequencer: Edit MIDI files
Sequencer: Record tracks
Sequencer: Add karaoke lyrics
Chords and Lyrics: Create accompaniment for a song
Style Editor: Simple editing
Style Editor: Advanced editing
Style Editor: Create a style from scratch
Style Editor: Create a style from a MIDI file
Multi-voices: Edit voices for Live and Sequencer usage
Using software synthesizers
Installing OMB on a Windows Tablet