programming with max/msp - Virtual Sound

Chapter 2P - Additive and vector synthesis
2.1 FIXED SPECTRUM ADDITIVE SYNTHESIS
To start things off, let’s create a patch for producing harmonic sounds in
Max/MSP using additive synthesis, with Figure 2.12 of the theory chapter as
our implementation guide. The diagram in that figure shows 10 oscillators,
all summed using a mixer, and so we will begin with 10 cycle~ objects that
will furnish the 10 sine waves, each producing a frequency which is an integer
multiple of the fundamental (in order to be harmonic). To calculate the
frequency values needed, we will simply multiply the frequency of the fundamental
by the first 10 integers. The resulting patch is shown in Figure 2.1
(02_01_additive.maxpat).
Fig. 2.1 The file 02_01_additive.maxpat
The number box at the top of the patch is used to set the fundamental frequency
for the entire patch, which is then passed to the 9 * operators using
successive integers to produce harmonic frequencies that are multiples of the
fundamental. The frequency of the fundamental and of the frequencies being
produced by these multipliers can be viewed in the 10 number boxes below,
which are themselves connected to as many cycle~ objects. These, in turn,
are connected to signal multipliers (*~) that rescale their outputs. Normally the
amplitude of a signal produced by cycle~ will have a peak value of 1, and
for this reason the value given to each multiplier serves to directly reflect the
relative amplitude of each harmonic (for example, 1.0 ∙ 0.5 = 0.5). The signal
multipliers enable each harmonic to have its own distinct amplitude, determined
by the value fed into its multiplier. Given that we have 10 oscillators, 10 values
completely specify the amplitudes to be used.
from “Electronic Music and Sound Design” Vol. 1 by Alessandro Cipriani and Maurizio Giri
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