The Kyma Language for Sound Design, Version 4.5

Like Random, OneOverF generates random numbers between zero and one, but it tends to generate
numbers that are close to one another for awhile, then make a large jump to a new number, then generate
numbers close to that one for awhile, etc. It gets its name from the shape of the distribution in the frequency
domain: 1/f or the inverse of the frequency; in other words, there tend to be large, slow changes
and small, fast changes. To hear what this sounds like, play 200 oneOverF. Try changing the value of the
seeds to hear a different set of events.
Controllers
Event Collections
Play 100 uniform + ctrl and then open it to see an example of how to specify continuous controller values
in a MIDI script. Here the controller !Morph is set to 0 at the beginning and is told to slide from its previous
value to a new random value on each note taking 10 steps to get there:
| r t |
r := Random newForKymaWithSeed: 2.
t := 0.
self controller: !Morph setTo: 0 atTime: 0 s.
100 timesRepeat: [
self
keyDownAt: t s
duration: (r next + 1) s
frequency: 3 c + (r next * 36 nn)
velocity: r next.
t := t + r next.
self controller: !Morph slideTo: r next steps: 10 byTime: t s].
Next, play 200 oneOverF + ctrl and then open it to see how it works. In this script, !Morph is set to zero
initially, and then slides to a value of one over the course of 40 seconds.
Sometimes it is more convenient to specify the MIDI events as collections of notes and rests, without
having to specify start times for each event. The actual start times can be inferred from the duration of the
Note or Rest and where it occurs in the collection of events. This corresponds more closely to written music
notation, where note and rest symbols arranged horizontally are interpreted as a sequence of events in
time (where each event’s start time occurs right after the previous event’s duration has expired), and
notes or rests arranged vertically are interpreted as all starting at the same time.
In the MIDI script language, an EventSequence is a collection of Notes, Rests, or other EventCollections
that occur one after another in time (corresponding to horizontal placement in music notation). Since you
can also construct sequences of other collections, you can create higher level structures as well. For example,
sequences of Notes and Rests could be collected in a measure; sequences of measures could be
collected into a phrase; sequences of phrases could be collected into sections; sequences of sections could
be collected into movements, etc. until you run out of traditional musical names for the structures(!)
An EventMix is a collection of Notes, Rests, or other EventCollections that occur all at the same time
(corresponding to vertical placement in music notation). Like an EventSequence, the EventMix is recursively
defined (i.e. you could have an EventMix of EventMixes), allowing you to define hierarchical
structures, somewhat analogously to the way you can define Sounds.
You can also create a generic EventCollection of Notes, Rests, or other EventCollections, specifying that
you haven’t yet decided whether the events should be simultaneous or sequential but will send a message
to the object later to specify actual start times and turn it into a sequence or a mix of other events.
EventSequence
Play the Sound called re-turn of phrase, and then open it so you can study the MIDI script (by the way, in
case you missed this earlier, you can use Ctrl+L to make any parameter field larger — an essential little
feature for viewing and editing these scripts).
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