De setup is defined in the file config.txt, you can change it in an editor. Lets take a look in it.


Midi ports with the specified word in its name are selected. If none matches then the last one is selected. Check with shell command "aconnect -io" which ports are available. If you haven't started any synthesizer or other MIDI software and the MIDI cable is plugged in then the MIDI USB interface will be the last listed and selected for both in and out.


Right hand keys for melody playing start with key 60 (middle C). Keys to the left are for playing chords


Recorded MIDI files are placed in the folder ./MidiFiles/
Stylefiles are loaded from the folder ./Styles/


Style that will be loaded initially.

Flute Duet

Multivoice that will be loaded initially.


Switch recording on.

Left on/off

Switch the left hand voice on. Key played in the chord area will produce sound.


Key 36 (lowest key on keyboard with 61 or 49 keys) will load this style (when attention key is down).


Key 60 (middle C) wil activate this multivoice (when attention key is down).

74:Transp down

Transpose 1 semitone lower. This function will be activated when this key is pressed while the attention key is down.


When this key is pressed all other keys will trigger the actions defined above.

Styles, multivoices and functions can be activated in three ways:

  1. Attach it to a keynumber as show above. OMBL will figure out if it is a styles, multivoice or function.
  2. Place it on its own like in the top part of this page. They will be activated at startup.
  3. Type it at run time and press return, you will need a computer keyboard attached, but not necessarily a monitor or mouse.

Instead of typing the name of an existing multivoice, you can also type the definition of a multivoice. It must start with 'i' followed by the number of a gm instrument and optional parameters. After the first instrument you can specify more instruments starting with "i" for layered (mixed) instruments or "l" for the left hand voice definitions.

Options for each instrument in the multivoice are:

o = play one octave lower
O = play two octaves lower
c = add close harmony (only for the first instrument)
w = add wide harmony (only for the first instrument)
d = add double harmony
v (followed by number 0-127) = set the volume for this instrument



This voice will be activated when key 36 is pressed in attention mode. It contains gm instrumentnumber 52 (ChoirAah) with double harmony. Left hand voice is not specified but will be strings by default.


The same key is assigned a multivoice with a flute (i73w) with wide harmony, layered with a violin (i40).

Now let's add some comma's and spaces for readability.

36:i18 c v90, i17 v70, i32 O v80, l16 v60

A rock organ (i18) with close harmony playing at volume level 90 is mixed with a percussive organ (i17) playing at volume 70 and a acoustic bass (i32) playing 2 octaves lower at volume 80. A draw organ (i16) playing at volume 60 is used for the left hand part.


Not enough control options for you? There is an alternative way. Download the demo of One Man Band v11, it is available for Windows, OSX and Linux (not for the Pi). Replace the omb.cfg in the startup folder with the omb.cfg in the ombl folder on the Pi. Change it to your needs using the OMB demo and then place it back on the Pi. Remove everything in the config.txt except for the definitions of the midi ports and folders. OMB Live on the Pi will now behave the same way as it did in OMB11.