about Study 3 sketch

Introduction

This sketch was created in the autumn of 2011 while developing some new features for Moritz’ Assistant Composer.

The barline, beam and note-extender features are described below in Structure:Bars 2-5.
The use of audio samples is described in connection with this sketch’s Palettes.

The audio samples used as models in Study 3 sketch are extracts from recordings of bird songs found at xeno-canto. The original recordings were cut, amplified, and sometimes slowed down using Audacity. Unfortunately, I have lost track of the original files, so am unable to say with certainty who made them, but I would like to thank xeno-canto for their wonderful site, and their permission to use these extracts here. Anyone interested in bird songs should definitely take a look at their site!

Scores

Structure

Bar 1: In all four scores, each of the eight staves in bar 1 contains a sequence of chords in the order they are defined in a corresponding palette. Recordings of the individual chords can be played in the Palettes documentation below.

Bars 2-5: One of Moritz’ original objectives was to enable writing (static, non-temporal information) to be used to compose high levels of temporal information.
Written barlines must exist because they are important for visual orientation, and they provide places at which systems can be broken. But barlines are not necessarily related to any temporal (audible) structure, and anyway belong to a particular level in the graphical information hierarchy. They should be treated as annotations, and not be allowed to interfere with other levels of temporal or graphical structure. This was not possible before, in Study 2.
As a test for developing this idea, bar 2 of Study 3 sketch contains parallel chains of chords (“melodies”) whose entry time is independent of their content. Each staff’s chain consists of its chords from bar 1 fit into the total duration of the "melody" without any intervening time. The music in bar 2 is repeated exactly in bars 3-5, but it is notated with two additional barlines, allowing the system to be broken at two additional points.
Continuation lines and cautionary chords are used to visually extend chords across barlines and systems. It would also have been be possible to use more traditional ties and tied chord symbols.

Similar arguments apply to beams. Beams are also visual aids, unrelated to the enclosed temporal (MIDI) information. Beams and barlines have different, independent functions, so there is now an option allowing them to cross or break each other when using the standard chord symbols.
Currently, beams can cross barlines but not system boundaries. This may change in a later revision.

Treating barlines as annotations (which are potential system breaks) not only simplifies the writing of composition algorithms, but should also be of use in other situations. For example when automatically transcribing MIDI files: First load the temporal structure (chords and melodies) then add the beams and barlines, and decide where the system breaks should be.

The graphic (2b2) symbols used in sketches 1b and 2b do not have beams or ties, but the MIDI information is still embedded in the same way. The Assistant Performer can therefore play all these scores, regardless of the symbol type.

Recordings

The following MIDI recording was created by the Assistant Performer using the sketch 1 score.
The other scores produce the same output, so this is the only MIDI recording of the whole score. Note that this sketch was intended as a test-bed for developing aspects of the Assistant Composer. In contrast to Study 2, its global form is unimportant. It is not a “composition”.

Study 3 sketch 1.mid

Note that while Windows Media Player seems to play MIDI files correctly, Quicktime 7.7.1 is unreliable. On my system (Windows Vista 64bit Ultimate) Quicktime sometimes (?) reacts too slowly to patch changes, and fails to play the final note in the file.

MP3

This is the mp3 recording presented on the scores. Recordings of the individual sounds composed in each palette, can be played in the Palettes documentation below.

Assistant Composer Settings

The Assistant Composer itself is likely to change again in future. The following screenshots and comments describe the settings used for Study 3 sketch in March 2012. Unexplained features should either be self-explanatory or explained elsewhere — for example in the latest Assistant Composer documentation or in the earlier Study 2b documentation.

Main Form

images/Study3Main.png

score pop-up: the settings for any of the other Study 3 sketch scores can be loaded by selecting a score name here.

chord type pop-up: ‘standard’ or ‘2b2’ symbols can be chosen here. The ‘minimum crotchet duration’ and ‘beams cross barlines’ options are available only when ‘standard’ chord symbols are chosen.

midi channels per voice per staff input field: The MIDI channels created by the algorithm are displayed in blue above the input box (in this case, channels 0, 1, 2, 3, 4, 5, 6, 7). This input field decides the number of staves per system, and allocates voices (MIDI channels) to each staff. (See the Assistant Composer or Study2c documentation.) In this case, it was decided simply to keep one channel per staff, but to reverse their order from top to bottom. When this field has been set, the help texts in the dialog adjust to the number of staves in the score.

krystals: Study 3 sketch does not use krystals to determine the positions of chords. Discovering that not all scores need to use krystals lead to the de-coupling of palettes and krystals at this top level of the Assistant Composer. Krystals are still required for ornament definitions, so there is still a compulsory krystal input field in the Ornament Palettes (see below).

Palette 1 (staff 8)

images/Study3Palette1.png
Durations are in milliseconds, most of the other units are integral values which can be used directly in MIDI messages. This is in contrast to the previous version of this Assistant Composer, which used percentage values.

MIDI Instruments button: opens a help window listing MIDI instrument numbers.

MIDI Pitches button: opens a help window listing pitch names and their MIDI pitch numbers.

midi buttons: This list of buttons is created dynamically, with one button per sound defined in the palette.
In contrast to the buttons in the above screen-shot, the following buttons actually work. They play the sounds composed in palette 1 as audio files converted from the original MIDI. (I am currently working on the direct performance of MIDI data in browsers.)
midi1 p1Midi2 p1Midi3 p1Midi4 p1Midi5 p1Midi6 p1Midi7 p1Midi8 p1Midi9 p1Midi10 p1Midi11 p1Midi12

audio buttons: This list of buttons is created parallel to the midi buttons. An audio file (.wav or .mp3) can be loaded into each of these buttons, to serve as a model for a sound being constructed in the palette. Study 3 sketch uses extracts from bird songs. Palettes 1-4 use the same three models (sounds made by cormorants). These models can be heard by clicking the first three of the following buttons.
p1Model1 p1Model2 p1Model3 p1Empty4 p1Empty5 p1Empty6 p1Empty7 p1Empty8 p1Empty9 p1Empty10 p1Empty11 p1Empty12

ornament settings: For details of how ornaments are constructed, see aboutStudy2b:Ornament construction.
images/Study3Palette1orn.png

Palette 2 (staff 7)

images/Study3Palette2.png
midi buttons: The following buttons play the sounds composed in palette 2 as audio files converted from the original MIDI.
p2Midi1 p2Midi2 p2Midi3 p2Midi4 p2Midi5 p2Midi6 p2Midi7 p2Midi8 p2Midi9 p2Midi10 p2Midi11 p2Midi12
audio buttons: Palettes 1-4 all use the following three models (cormorant sounds):
p2Model1 p2Model2 p2Model3 p1Empty4 p1Empty5 p1Empty6 p1Empty7 p1Empty8 p1Empty9 p1Empty10 p1Empty11 p1Empty12

ornament settings: For details of how ornaments are constructed, see aboutStudy2b:Ornament construction.
images/Study3Palette2orn.png

Palette 3 (staff 6)

images/Study3Palette3.png
midi buttons: The following buttons play the sounds composed in palette 3 as audio files converted from the original MIDI.
p3Midi1 p3Midi2 p3Midi3 p3Midi4 p3Midi5 p3Midi6 p3Midi7 p3Midi8 p3Midi9 p3Midi10 p3Midi11 p3Midi12
audio buttons: Palettes 1-4 all use the following three models (cormorant sounds):
p3Model1 p3Model2 p3Model3 p1Empty4 p1Empty5 p1Empty6 p1Empty7 p1Empty8 p1Empty9 p1Empty10 p1Empty11 p1Empty12

ornament settings: For details of how ornaments are constructed, see aboutStudy2b:Ornament construction.
images/Study3Palette3orn.png

Palette 4 (staff 5)

images/Study3Palette4.png
midi buttons: The following buttons play the sounds composed in palette 4 as audio files converted from the original MIDI.
p4Midi1 p4Midi2 p4Midi3 p4Midi4 p4Midi5 p4Midi6 p4Midi7 p4Midi8 p4Midi9 p4Midi10 p4Midi11 p4Midi12
audio buttons: Palettes 1-4 all use the following three models (cormorant sounds):
p4Model1 p4Model2 p4Model3 p1Empty4 p1Empty5 p1Empty6 p1Empty7 p1Empty8 p1Empty9 p1Empty10 p1Empty11 p1Empty12

ornament settings: For details of how ornaments are constructed, see aboutStudy2b:Ornament construction.
images/Study3Palette4orn.png

Palette 5 (staff 4)

images/Study3Palette5.png
midi buttons: The following buttons play the sounds composed in palette 5 as audio files converted from the original MIDI.
p5Midi1 p5Midi2 p5Midi3 p5Midi4 p5Midi5 p5Midi6 p5Midi7 p5Midi8 p5Midi9 p5Midi10 p5Midi11 p5Midi12
audio buttons: Palette 5's models are 9 events taken from blackbird songs.
p5Model1 p5Model2 p5Model3 p5Model4 p5Model5 p5Model6 p5Model7 p5Model8 p5Model9 p1Empty10 p1Empty11 p1Empty12

ornament settings: For details of how ornaments are constructed, see aboutStudy2b:Ornament construction.
images/Study3Palette5orn.png

Palette 6 (staff 3)

images/Study3Palette6.png
midi buttons: The following buttons play the sounds composed in palette 6 as audio files converted from the original MIDI.
p6Midi1 p6Midi2 p6Midi3 p6Midi4 p6Midi5 p6Midi6 p6Midi7 p6Midi8 p6Midi9 p6Midi10 p6Midi11 p6Midi12
audio buttons: Palette 6's models are 4 warbles taken from blackbird songs.
p6Model1 p6Model2 p6Model3 p6Model4 p1Empty5 p1Empty6 p1Empty7 p1Empty8 p1Empty9 p1Empty10 p1Empty11 p1Empty12

ornament settings: For details of how ornaments are constructed, see aboutStudy2b:Ornament construction.
images/Study3Palette6orn.png

Palette 7 (staff 2)

images/Study3Palette7.png
midi buttons: The following buttons play the sounds composed in palette 7 as audio files converted from the original MIDI.
p7Midi1 p7Midi2 p7Midi3 p7Midi4 p7Midi5 p7Midi6 p7Midi7 p7Midi8 p7Midi9 p7Midi10 p7Midi11 p7Midi12
audio buttons: Palette 7's models are 4 chirrups taken from blackbird songs.
p7Model1 p7Model2 p7Model3 p7Model4 p1Empty5 p1Empty6 p1Empty7 p1Empty8 p1Empty9 p1Empty10 p1Empty11 p1Empty12

ornament settings: For details of how ornaments are constructed, see aboutStudy2b:Ornament construction.
images/Study3Palette7orn.png

Palette 8 (staff 1)

images/Study3Palette8.png
midi buttons: The following buttons play the sounds composed in palette 8 as audio files converted from the original MIDI.
p8Midi1 p8Midi2 p8Midi3 p8Midi4 p8Midi5 p8Midi6 p8Midi7 p8Midi8 p8Midi9 p8Midi10 p8Midi11 p8Midi12
audio buttons: Palette 8's models are 7 ruminations taken from blackbird songs.
p8Model1 p8Model2 p8Model3 p8Model4 p8Model5 p8Model6 p8Model7 p1Empty8 p1Empty9 p1Empty10 p1Empty11 p1Empty12

ornament settings: For details of how ornaments are constructed, see aboutStudy2b:Ornament construction.
images/Study3Palette8orn.png