[stringnode] is a computer-assisted composition tool, specifically developed for the writing of «...como la pólvora...» (2022) attractors for amplified string quartet. It consists of two parts, a MaxMSP patch/app and M4L audio device, for sequencing and playback of undulating, harmonic-touch fingering patterns. The pattern sequencing is done through .bell scripts containing the instructions for how to build each pattern sequence.
Click here for an early version preview of [stringnode].
[stringnode] sampler is a simple MaxForLive device that receives playback information from the sequencer via OSC messages. To use the sampler, simply drag it into 4 separate Ableton Live audio tracks, and assign a different string instrument for each of them.
NOTE: the OSC port (3000) is hard-coded into both the sampler and sequencer.
[stringnode] sequencer transcribes pattern sequences from a given .bell script, using the MaxMSP package bach. All string and fingering patterns are arbitrarily set to have a triangular wave shape.
To load a script, select a folder containing .bell files and choose the script using the sequencer's menu. To play a specific pattern use the marker menu.
For convenience, the sequencer also diplays two streams of information about each sequence:
- The parametric features of each pattern (see
<pattern>format section below), as a list:
<voices> <beat_unit> <num_strings> <num_bows> <hop_size> <reps> <gap>- The periodicity, with its 1st derivative, for each pattern.
For some examples, take a look at the bell_scripts folder.
The structure of a .bell script is hierarchical, and can include 4 different blocks of information at the main level — pattern sequences, tempo changes, fret structures, and quantization information. The general structure of a script using all 4 types of main-level blocks would look something like this:
[ `tempo <BPM> ]
[ `frets <fret_list> ]
[ `seq <seq_onset_1>
[<pattern_1>]
[<pattern_2>]
]
[ `seq <seq_onset_2>
[<pattern_1>]
[<pattern_2>]
]
[ `quantization
[<quantization_info>]
]Notice that each main-level element starts with a keyword, prepended with a backtick (`)
The formats for each element in the previous example are explained below:
<tempo>format (optional):<tempo>is specified as a quarter note BPM value. More than one<tempo>can be included in the same script to change the tempo of individual<seq>or<pattern>elements. If not specified, the default is120. For instance:
[ `tempo 130]<frets>format (optional):<frets>are specified as a list of integers, which determines the available fingerings in semitones for the patterns in all 4 instruments. For instance`frets 0 2 3 5 7 8 10 12would result in a minor scale within each and all strings. The maximum fret value supported for playback with[stringnode]sampler is12. More than one<frets>element can be included in the same script to change the fretting of individual<seq>or<pattern>elements. If not specified, the default fretting is(0 2 4 5 7 9 11 12). For instance:
[ `frets 0 2 3 5 6 8 9 11 12]<seq>format: a<seq>is a list containing a consecutive series of one or more<pattern>elements (and optionally<tempo>and/or<fret>elements), all preceded by the`seqkeyword and the onset for the entire<seq>. More than one<seq>can be included in the same script. For instance:
[ `seq 0
[[3] [2] [0] 1/16 4 2 0 2 0 ]
[[3] [2] [0] 1/16 3 3 0 2 0 ]
]
[ `seq 1/4
[[1] [2] [0] 1/16 2 4 0 2 0 ]
[[1] [2] [0] 1/16 3 3 0 2 0 ]
]or changing tempo within a sequence:
[ `seq 0
[ `tempo 120 ]
[[2] [3] [0] 1/16 2 2 0 2 0 ]
[ `tempo 130 ]
[[2] [3] [0] 1/16 2 2 0 2 0 ]
[ `tempo 140 ]
[[2] [3] [0] 1/16 2 2 0 2 0 ]
]NOTE: the sequence <onset> is specified as a tempo-relative unit — e.g. 3/4, 5/8, etc.
-
<pattern>format: each<pattern>is built from 9 parameters, in the following order:- A list of
<instr_ids>, specifying which instruments are playing the pattern. The indices range from 1 to 4, corresponding to violin I, violin II, viola, and cello, respectively. - A list of
<fret_positions>, specifying the starting position for the pattern, for each voice/instrument. The number of positions must match the number of<instr_ids>. - A list of
<string_offsets>, specifying the offset for the initial string in the pattern, for each voice/instrument. The number of string offsets must match the number of<instr_ids>. By default, all patterns start on string 4. - The tempo-relative
<beat_unit>for all values in the pattern — e.g. 1/16, 1/8, 1/4, etc. - The number of strings (
<num_strings>) used in the pattern. - The number of bowings (
<num_bows>) per string. - The amount of beat rests around the center of the pattern (
<hop_size>), when using more than 1 voice. - The amount of repetitions (
<reps>) for the pattern. - The tempo-relative beat unit for the rest (
<gap>) separating the current<pattern>from the next.
For instance:
- A list of
## instr_id posns str_offset beat numstr bows hopsize reps gap
[[3] [2] [0] 1/16 4 2 0 2 0 ]<quantization>format (optional):<quantization> is a list specifying tempo, time signature(s), and number of bars for each time signature, when a specific metric configuration is needed. For instance:
[ `quantization
## tempo
[120
## time_sig num_bars
[4 4 1]
[6 8 2]
]
[160
[3 4 3]
[9 16 4]
]
]Finally, note that any bell-compatible synthax can be used to algorithmically generate sequences and/or patterns — e.g. for/while loops, native and user-defined functions, variable assignment, comments, etc. For instance:
## [stringnode] bell script example
[ `tempo 150]
[ `frets 0 1 3 4 6 7 9 10 12]
[ `seq 0
($bows = 1...6;
for $b $i in $bows collect
($unit = ($i%3)+1;
[[1...3] [3 :* 3] [rev(0...2)] $unit/16 2 $b 0 1 0])
)
][stringnode] is distributed under the terms of the GNU General Public License version 3 (GPL-v3.0).
[stringnode] was developed using the following third-party dependencies:
bach(v0.8.1.4)