Section 5 Flashcards
How does sound come about?
From pressure fluctuations in the air
What determines the loudness of sound?
The amplitude of the sine waves that represent the air fluctuations
What is loudness?
The psychological aspect of sound related to perceived intensity or amplitude
How is amplitude measured?
Decibels
What does dB = 0 mean?
The pressure fluctuation corresponds to the minimal auditory sound for most people
TRUE/FALSE
dBs are more reflective of subjectively perceived sound than actual sound pressure
true
How does dB if sound pressure increases by x10?
Increases by +20
What is intensity of sound?
Corresponds to the energy of the sound wave when it hits a 2D surface, such as the eardrum
What is pitch?
The psychological aspect of sound related mainly to the fundamental frequency
What do we call sounds that only have one frequency?
Pure tones
Sounds that have a lower frequency have a _______ (lower/higher) pitch
lower
What is a spectrum of sound?
It’s an easy way of breaking down complex sounds using bars whose height represents the amplitude and the position on the X axis represents which frequency that sound is at
What is a harmonic spectrum?
The spectrum of a complex sound in which the energy is integer multiples of the fundamental frequency
What is a fundamental frequency?
The lowest-frequency component of a complex periodic sound
What does it mean if different spectra of complex sounds have the same fundamental frequency?
They will all have the same pitch
If several complex sounds have the same pitch, does that guarantee they will have the same loudness?
No, loudness will depend on the amplitude differences
What is timbre?
The psychological sensation by which a listener can determine that two sounds with the same loudness and pitch are dissimilar
If two sounds have different timbres, what does that tell us about their harmonic spectrum?
Their spectra are different
What is a missing-fundamental effect?
The fundamental frequency is missing in the harmonic spectrum, but the pitch listeners hear still corresponds to that fundamental frequency
How can we hear the fundamental frequency even if it is absent in the spectrum?
The superposition of the different harmonics will recreate a peak that has the frequency of the missing fundamental
Describe audibility of a sound
The combination of frequency and amplitude
What is an equal-loudness curve?
A graph plotting sound pressure level (dB) against the frequency for which a listener perceives constant loudness
List the three sections that make up the ear
Outer, middle, and inner
What structures make up the outer ear?
Auditory canal and pinna