programming with max/msp - Virtual Sound

3.1
360
Practice
Fig. 3.6 The rand~ object
Paragraph 3.1 - Sound sources for subtractive synthesis
Obviously, this generator produces a spectrum that varies according to the
frequency setting; it shows a primary band of frequencies that range from 0
Hz up to the frequency setting, followed by additional bands that are gradually
attenuated and whose width are also equal to the frequency setting. Figure 3.7
shows this interesting spectrum.
Fig. 3.7 The spectrum generated by the rand~ object
In the example, we can see that the frequency of the rand~ object is 5,512.5 Hz
(a quarter of the maximum frequency visible in the spectroscope in the figure),
and the first band goes from 0 to 5,512.5 Hz. After this come secondary bands,
progressively attenuated, all 5,512.5 Hz wide. Changing the frequency of rand~
changes the width of the bands as well as their number. If you double the
frequency to 11,025 Hz, for example, you will see precisely two wide bands, both
11,025 Hz wide.
Another noise generator is vs.rand0~ 5 (the last character before the tilde is
a zero), which generates random samples at a given frequency like rand~, but
that doesn’t interpolate. Instead, it maintains the value of each sample until a
new sample is generated, producing stepped changes in value. The spectrum of
5 You should know from preceding chapters that the “vs” at the beginning of this object’s name
means that it a part of the Virtual Sound Macros library.
from “Electronic Music and Sound Design” Vol. 1 by Alessandro Cipriani and Maurizio Giri
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