Fundamentals of Speech Hearing Language- Exam 1

complex tones

two or more component frequencies that are harmonically related

complex waves make up

most of the sounds you hear, including speech

periodicity means

the cycles of energy are regular and repetitive

complex sounds can be

periodic or aperiodic

a transient sound is

instantaneous a

a continuous sound is

steady

the lowest frequency of a complex periodic sound is called the

fundamental frequency

higher harmonics reflect

shorter vibrating segments

harmonic means

an overtone acoompanying a fundamental tone at a fixed frequency

fourier’s basic principle

all complex periodic waveforms can be analyzed into a sum of harmoincs

constructive interference

if sounds are in phase, they are added to make a more intense sound

destructive interference

if sounds are out of phase, they are added to make a less intense sound.

psychoacoustics

study of relationship between physical properties of stimulus and our subjective experience of the stimulus

pitch

perceptual correlate of frequency; affected by intensity

Loudness

perceptual correlate of intensity; affected by frequency

physical qualities of sound includes

fundamental frequency, amplitude/ intensity and duration.

perceptual characteristics of sound

pitch, loudness and how long

frequency

a measurable characteristic of acoustic signals

what unit is pitch measured in?

Mel Scale

resonance

increase in vibration when a force is appleid at a natural frequency of the medium

resonator

object or medium set into vibration

why is resonance important?

aids vowel discrimination, allows some frequencies to be magnified and amplified.

physics

science that deals with matter, energy, motion and force

acoustics

a branch of physics that deals with the production, control, transmission, reception and effects of sound

bioacoustics

combination of biology and acoustics in the study of sound production and perception in animals and humans

what category does human speech fall into?

bioacoustics

energy

the ability( or power) to do work

work

the force needed to move a mass a certain distance in a certain amount of time

inertia

the resistance of any physical object to a change in its state of motion or rest

elasticity

the property of a material that returns it to it’s orignal shape after it has been changed by some external force

Stiffnes

the resistance of an elastic body to change by an applied force; the greater the stiffness, the greater the force required to displace it

intensity

power per unit area; usually measured in watts/ cm2

pressure

the force acting on a specific surface area. Usually measured in pascal

volume

amount of space in 3D

density

the amount of mass per unity of volume

boyles law

as volume decreases, pressure increases

sound has no

physical substance, mass or weight

air particles travel in

brownian motion

ambient pressure

the constant pressure created by air molecules

what is requried for sound?

source of energy, force to keep it moving, medium of transmission

areas of compression

molecules are closer together; more air pressure

areas of rarefactoin

molecuels are farther apart; less air pressure

inverse square law

sound intensity is inversely proportinoal to the square of the distance from the sound source

friction

Resitance of one Surface moving over anouther.

Rf stands for

restoring forces

RF elasticity is strongest when

inertia is weak

inertia is strongest when

RF elasticity is weak

sound disturbances are characterized as

waves

each individual vibration is called a

cycle

the number of cycles completed in one second is called the

frequency of vibration

waveforms are

common graphic representations of sound that displayes how amplitude varies with time and represents molecular motion

wavelength

distance travled during one cycle

period

duration of one cycle

amplitude is the

magnitude of displacement of an object

The decibel measures

the relative intensity between two sounds

decibles are a unit used to express

intensity or pressure of sound

speed of sound is assumed to be

344 m/s

low frequencies have

longer wavelengths and travel well through barriers

high frequencies have

shorter wavelengths and tend to reflect off barriers