programming with max/msp - Virtual Sound

Chapter 2P - Additive and vector synthesis 2P
ACTIVITIES
Using the patch 02_01_additive.maxpat, create two presets, one that has the
amplitudes of the odd harmonics set to 1, and those of the even harmonics set
to 0. Apart from timbre, what is the obvious difference? Why?
Continuing to use 02_01_additive.maxpat (and referring to the discussion of
missing fundamentals in Section 2.1T), begin with a spectrum in which the
amplitudes of all harmonics are 1, and then zero out the amplitude of the
fundamental. Listen for the illusion that the zeroed fundamental appears to be
present. Try reducing the amplitude of successive harmonics, one by one. At
what point can you no longer perceive the fundamental?
PHASE
We now take on a topic discussed at length in Section 2.1T (Section 2.1 of
Chapter 2T), the phase of a periodic waveform. It is a basic concept that will
develop over many chapters; because of this, it is important to understand
how phase is managed using Max/MSP. Probably you have noticed that the
cycle~ object has two inlets: the left, as we already know, allows us to set
the frequency, and the right allows us to set the normalized phase, a phase
that is expressed as a value between 0 and 1 (rather than a value between 0
and 360 degrees or between 0 and 2π radians, both of which we encountered
in the box dedicated to phase in Section 2.1T).
Build the patch shown in Figure 2.2 in a new Patcher Window.
Fig. 2.2 Constructive and destructive interference
We have two cycle~ objects at 440 Hz, the second of which has two message
boxes, containing the numbers 0.5 and 0, connected to its right inlet (its
phase inlet, as we just learned). Start the patch by clicking on “startwindow”
and raising the gain~ fader: you will hear a perfectly in-phase A440 generated
by the two oscillators.
from “Electronic Music and Sound Design” Vol. 1 by Alessandro Cipriani and Maurizio Giri
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