Alter Aeon Online Help

Keywords are:  'notation'

perform [instrument] <args> - play a musical number with an instrument

perform notes    - the number of notes you can play in a performance

The musical notation is as follows:

Single notes have 2 to 4 components:

Accidentals: # for sharp, & for flat (this is optional)
Pitch:       a-g baseline, prefix + for high notes, - for a low notes
Duration:    1-9 beats

Note: rhythm instruments cannot have a note designated and will
always play the same note. Only a duration needs to be designated.

Example: 
#+a4 - high A sharp for 4 beats

Chords have 4 to 5 components:

Mode:       M - major, N - minor, U - augmented, I - diminished
Accidental: # for sharp, & for flat (this is optional)
Key:        root note of the chord, same usage as single notes
Duration:   1-9 beats

Example: 
M+c3  - High C major chord for 3 beats

Rests have 2 components:

R (for rest)
Duration: 1-9 beats

Example:
R2  - Rest 2 beats

Advanced options:

Starting a performance with 's3' increases the duration of notes by 50%
to approximate a 3 beat measure.

Duration for individual notes can be substituted with "t", which has a
very short duration. Multiple notes, chords or rests can be parsed in
this way in succession to produce something approximating a trill.

For extended keyboard instruments, you can play two octaves above or
below the tonic with '>' and '<' in place of of '+' and '-'.

Chords can be inverted by adding 'v' or 'o' behind the letter notation,
before the duration. The former designates a first inversion, the latter
a second inversion.

For polyphonic instruments with an extended range, you can add an
additional note or chord. Use an 'l' in place of a duration for the first
note or chord, then add the notation for the second note or chord as
normal, with no space between the two. For example 'm+alme4' would play
both the high A major and E major keys.

You cannot start or end performances with a rest, nor can you have
two or more rests in a row. A rest will not stop a drone from playing.