Glossary#
An alphabetical reference of key terms used throughout the book. Terms marked
with the {vocab} role in the text link to their definition here. Entries are
sorted automatically, so this page doubles as the book’s global index.
A
- additive synthesis#
Building a complex tone by summing sinusoidal harmonics with chosen amplitudes.
- amplitude#
The peak deviation of a waveform from its rest (zero) value.
- angular frequency#
The rate of phase accumulation of a sinusoid of frequency \(f\), \(\omega = 2\pi f\), measured in radians per second.
B
- basic sinusoid#
The most elementary periodic function, \(x(t) = a \sin(2\pi f t + \phi)\). It sounds like a pure tone and is the building block from which all periodic sound can be composed.
F
- Fourier series#
The representation of a periodic signal as a sum of sinusoidal harmonics.
- frequency#
The number of cycles a periodic signal completes per second, measured in hertz (Hz). It is the reciprocal of the fundamental period, \(f = 1/t_0\).
- fundamental period#
The smallest strictly positive interval \(t_0\) over which a periodic signal repeats; the duration of one cycle.
H
- harmonic#
A sinusoidal component whose frequency is an integer multiple of the fundamental frequency.
- Hertz#
The unit of frequency, abbreviated Hz; one hertz is one cycle per second.
I
- initial phase#
The constant offset \(\phi\), in radians, that shifts a sinusoid’s starting point within its cycle.
- instantaneous phase#
The total phase of a sinusoid at time \(t\), \(\theta(t) = 2\pi f t + \phi = \omega t + \phi\), in radians.
P
- periodic#
A signal is periodic if it repeats at a fixed interval in time — that is, \(x(t) = x(t + T)\) for some period \(T\).
- phase#
A quantity characterizing the current position within a cycle of a sinusoid.
- phase increment#
In wavetable synthesis, how far the read position advances through the table per output sample.
T
- timbre#
The tonal “color” of a sound — what distinguishes two tones of the same pitch and loudness, largely determined by the relative amplitudes of their harmonics.
W
- wavetable#
An array storing a single cycle of a waveform, sampled at \(M\) points, used to synthesize a tone by repeated lookup.
- wavetable synthesis#
Synthesizing a tone efficiently by precomputing one cycle of a waveform as a wavetable, then reading through it repeatedly at the rate that yields the desired frequency.