The Kyma Language for Sound Design, Version 4.5

ases of those higher harmonics, artifacts of one of the basic facts of life in the digital domain: you cannot
represent any frequencies above half of the sampling frequency.
Next let’s see how the sawtooth is created before it is distorted by the Gain module. Double-click the icon
named 3 key-mapped saws. This is a Mixer with three inputs: saw1, saw2, and saw3. The Mixer adds the
outputs of all three of these Sounds and then multiplies the sum by the current value of !Volume. Since
the Gain subsequently multiplies that result by ten and the value of !Volume can range from zero to one,
the end result is that the sum can be multiplied by a number in the range of zero to ten, depending on
where you set the value of !Volume.
So far all we’ve seen is adding, filtering, enveloping, and distortion. When do actually get to the part that
generates sound? Funny you should ask (did you?), because that is what we finally get to with this next
and final level; double-click on saw1 to see its parameters. A KeyMappedMultisample uses an entire
folder full of samples as its source material and uses the policy described in the Mapping parameter to
map different samples to different MIDI key numbers or ranges of key numbers. In saw1, each sample
from the folder is mapped to the range of pitches specified in the header of the samples file. Why use different
samples for different pitch ranges? Because of that fundamental law of the digital domain: you
can’t represent any frequencies above half the sampling rate. So the higher the fundamental pitch, the
fewer harmonics its waveform can have, because those harmonics, being at frequencies that are multiples
of the fundamental, can quickly get high enough to exceed the half sample rate limit. That’s why saw1
uses waveforms with many harmonics for the bass notes, and waveforms with only a few harmonics for
the really high frequencies.
Take a look at the Frequency of saw1 and compare it to the same parameter field in saw2 and in saw3.
If it is difficult to read everything that is in the Frequency field, position the cursor on the center line
dividing the signal flow graph from the parameter fields until the cursor turns into a double-arrow
pointing up and down. Then use the mouse to drag that center line upwards, making all the parameter
fields larger so you can read their contents.
Notice that the Frequency values differ by the value of !Detune1 and !Detune2. By making these
three “oscillators” slightly out of tune with each other, you can get them to sometimes reinforce each
other, sometimes cancel each other, and generally get a more dynamic, evolving timbre than you would
be able to get out of fixed frequency oscillators. Try this out right now. Select 3 key-mapped saws (the mix
of the three sawtooth oscillators) and choose Oscilloscope from the Info menu. Experiment with different
values for !Detune1 and !Detune2.
Now, what about this expression in the Frequency field?
!KeyNumber smoothed nn + !Detune1 nn
This is saying that the frequency is the MIDI key number in units of note number (nn) plus some fraction
of a half step that depends on the value of !Detune1. The smoothed means that when you change from
one note number to another, it will take 100 milliseconds to make the transition, rather than making it
instantaneously.
Modifying the Example
Now it’s time to start mutating the Sound in order to both gain a deeper understanding of how it is put
together and to start building your own Sound library. First, close the Sound editor, and make a duplicate
of delayed saws so you can retain the original Sound and make your changes to the duplicate. (Do this by
selecting the icon and using Ctrl+D for duplicate). To change the name of your new Sound, make sure
DuplicateOfDelayed saws is still selected, and hit Enter. This gives you a dialog where you can enter a
new name for the Sound; you might as well call it ‘my saws’, just to be stunningly original.
In order to keep track of which Sounds came with the system and which ones you design yourself, you
can create a new Sound file (by typing Ctrl+N and selecting Sound file as the file type) and drag the my
saws icon into this new window. Save it on the disk, creating a new folder for the purpose called my examples
and giving the file itself a memorable name like my analog.
At this early stage, this may seem like just an exercise, but in fact, it is a good idea to start using Sound
files to categorize and organize your new Sound designs from the very beginning. As soon as you start
tweaking Sounds, you start hearing things you’ve never heard before, and even if you are diligently fol-
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