[LAU] [LAD] [LAA] Mamba - Virtual Midi keyboard for Jack Audio Connection Kit release 1.8

David Kastrup dak at gnu.org
Tue Nov 24 11:40:02 CET 2020

Hermann Meyer <brummer- at web.de> writes:

> Mamba release v1.9 is out
> Mamba is a Virtual MIDI keyboard with some extended, unique features.
> This is a quick fix release as I've forgotten to implement jack MIDI
> input forwarding to ALSA MIDI output.

Stupid question: I see you implemented different national keyboard
layouts that basically define a mapping from characters to physical key
positions.  I think that raw X11 key events might actually encode key
positions (or numbers based on a particular arrangement of keys) but
maybe they are not easily available at the layer your key events arrive.

But the actual question is a different one: have you considered offering
a chromatic button accordion arrangement "on top" of that national

Basically it would mean that a chromatic scale is encoded as

zsexdrcftvgybhunjimko,lp.;[/'] for C system (with a qwerty keyboard,
starting at C) and
qazwsxedcrfvtgbyhnujmik,ol.p;/ for B system (again, starting at C).

Finnish G system uses the same scale as C system apart from starting
with C♯ rather than C in the first row.  I can provide images if
necessary (there are some at

Modern CBA keyboards tend to have 5 rows but the inner 2 rows are
repeats for making transposition and chord fingerings easier and
basically every player can get along without them at least when doing
note entry.  So whether to offer more than 3 rows depends on whether
there is an actual use for the numbers and function keys.

The main advantage for CBA players of course is easier entry.  The main
advantage for everyone else would be access to more notes at the same

David Kastrup

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