PSY 131 midterm 2 Flashcards
Transient signals/ click stimulus/ spectral splatter
brief acoustical signal in which the sound level changes abruptly
Perceptual Beats
periodic change in overall loudness of a tone; occurs if change in f is less than 15-20 Hz
acoustic beats
periodic increase + decrease in amplitude caused by superposition of 2 sine waves of different frequencies
amplitude modulation
multiplication of two signals results in a change in temporal envelope
frequency modulation
addition of two signals does not change temporal envelope
sidebands
two frequency components
noise
random sequence of amplitude variations over time
low pass filter
passes all frequencies below cutoff
high pass filter
passes all frequencies above cutoff
bandpass
passes all frequencies between upper and lower cutoff
bandstop
attenuates all frequencies between upper and lower cutoff
linear system
output of the system is linear function to the input
nonlinear system
nonlinear relationship between input and output
can introduce new frequency components
difference tone
type of intermodulation distortion (equal to the change of f of two frequency components)
intermodular distortion
results from nonlinear system: the interaction of two or more frequency components
compression
reduce range of sound intensities in the output
Driver
catalyst that causes vibration of sound source (hand, hammer, etc)
generator
the medium in or on which a standing wave of vibration is created and maintained (string, vocal cords)
resonator
an object that attenuates or amplifies the signal from a generator
free vibration
ex: plucked string, as soon as string is set into motion, damping occurs due to impedance (measure of how much medium resists movement)
forced vibration
ex: shouting at an undamped guitar; if fundamental frequency of driver is close to the natural frequency of the string, the string will resonate/vibrate
outer ear function
protection, sound localization, modification of sound waves
ear canal
resonant properties cause us to have greater sensitivities to frequencies between 1kHz and 6 kHz
middle ear parts
malleus - incus - stapes