Notes, Chords and Chord-Seqs
There are three harmonic objects : notes, chords, chord-seqs. Chord-seqs are successions of chords.
- A note is a unique pitch.
- A chord is a list of notes.
- A chord-seq is a list of chords.
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A note, a chord and a chord-seq.
General Features
Parameters
Harmonic objects have a number of common parameters. Chords and chord-seqs have specific parameters.
Objects
Parameter
Input Name
Value
—|—|—|—
All
Pitch
“midic”
Midicents
All
Dynamics
“vel”
1 -> 127
All
Duration
“dur”
Milliseconds
All
Timbre
“midichannel”
1 -> 16
Chords and chord-seqs
Offset
“offset”
Milliseconds
Chord-seqs
Onset
“onset”
Milliseconds
Chord-seqs
Legato
“legato”
Milliseconds
The inputs order varies depending on their significance to the object.
Input Values
-
Note inputs accept atoms only, that is, a simple value without parenthesis. A single pitch, and its corresponding parametric values as well, must be expressed by an atom.
-
** Chord ** inputs accept atoms and lists . A chord consisting of a single note is expressed by an atom. A chord consisting of a set of notes must be expressed by a list.
-
** Chord-seq ** inputs accept elementary lists and lists with sub lists . A chord-seq consisting of a succession of notes is expressed in an elementary list. A chord-seq consisting of a succession of chords is expressed by a list with sub lists. The elements of one sub list belong to the same chord.
The “ legato “ input accepts atoms only : a single legato value is applied to all the elements of the chord-seq.
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As chord-seqs rather expect sub lists, lists are converted into sub lists when outputs are evaluated.
Here, the three first values of the output list stand for distinct chords. They are converted into sub lists.
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Note
The default data structure format can be checked by hovering the mouse over the inputs of a box.
Chord and Chord-Seq Specific Features
Offsets and Onsets
Chords and chord-seq have specific parameters : “offsets” and “onsets”, which can become easily confusing.
- The onset represents the position of the first note of a chord .
- The offset represents the delay between this first note and the following note(s ). A chord can “unfold” in time, with an arpeggio for instance.
Offsets are visible when opening the editor of a chord or chord-seq.
Each chord of the chord-seq has one onset, and one offset per note.
Legato
A chord-seq has a supplemental input : the “ legato “ input. All chords
have the same legato percentage. Hence, the “legato” input only accepts atoms.
It is displayed in the score editor via the duration menu item of the editor
control.
This value doesn’t apply to notes or chords added subsequently via the score editor.
Displaying Parametric Values :
Chords and chord-seqs : Matching List Structures
The list structures of each slot of a chord or chord-seq don’t have to be strictly similar. Objects manipulate the lists assigned to each of their parameters to produce compatible lists.
If lists don’t have the same number of elements, shorter lists are completed to fit the longest list(s) :
- by repeating the last element
- by applying the same time difference to all elements, in the case of onsets .
If a list has too many elements, the last elements are suppressed.
In any case, pitches is the reference list.
The object returns compatible and coherent pattern.
References :
Contents :
- OpenMusic Documentation
- OM User Manual
- OpenMusic QuickStart