Chapter 10 Flashcards
sound waves
undulating displacement of molecules caused by changing pressure
frequency
number of cycles that a wave completes in a given amount of time
hertz (Hz)
measure of frequency (repetition rate) of a sound wave; 1 hertz is equal to 1 cycle per second
3 physical attributes of sound waves
frequency, amplitude, complexity—>produced by the displacement of air molecules
how fast do sound waves travel?
fixed speed of 1100 feet per second
Frequency & pitch perception
the rate at which sound waves vibrate is measured as cycles per second, or hertz
amplitude and perception of loudness
intensity of sound is usually measured in decibels
complexity and timbre
mixture of frequencies; a sound’s complexity determines its timbre
timbre
perception of sound quality; perceived characteristics that distinguish a particular sound from all others of similar pitch and loudness
low pitch sounds
have slow wave frequencies (fewer cycles per second)
high pitched sounds
have faster wave frequencies (many cycles per second)
range of human’s hearing
20-20,000 hertz
perfect (absolute) pitch
runs in families; suggests genetic influence
amplitude
intensity of a stimulus; in audition, roughly equivalent to loudness, graphed by increasing height of a sound wave
decibel (dB)
unit for measuring the relative physical intensity of sounds
what causes increased loudness?
increase compression of air molecules intensifies the energy in a sound wave, which amps the sound—makes it louder
pure tones
sounds with a single frequency
complex tones
sounds that mix wave frequencies together in combinations
fundamental frequency
the rate at which the complete waveform pattern repeats
overtones
set of higher-frequency sound waves that vibrate at whole-number (integer) multiples of the fundamental frequency
noise
sounds that are aperiodic or random
frequency of waves
pitch
height (amplitude) of waves
loudness
left temporal lobe
speech