H - Sound Theory Flashcards
longitudal wave
disturbance moving along the direction of a wave
transverse wave
disturbance moving perpendicular to the direction of a wave
cycle of a waveform
period of compression and rarefraction
compression
increase in air molecules above normal pressure level
rarefaction
decrease in air molecules below normal pressure level
amplitude is perceived as…..
the loudness of a wave
frequency is perceived as……..
the pitch of a wave
the frequency of a wave is
the pressure of a wave, the time it takes to complete a full cycle
an octave is a….
doubling/halving of frequency
ear tuning is when…..
different frequencies are perceived at different levels
speed of sound is affected by…..
density/ temperature/ altitude
higher density means sound travels……
sound travels faster
sound travels fastest in which order….. gases/liquids/solids
solids then liquids then gases
in warmer air sound travels….. than in colder air
sound travels faster
at higher altitude sound travels……
slower
reflection of sound waves….
sound bouncing back of a surface
diffraction of sound waves….
sound bending and changing directions§
absorption of sound waves…..
how sounds are lost as they reach an object
diffusion of sound waves…..
the scattering of sound waves
refraction of sound waves…..
the change in direction of sound waves
white noise is….
all frequencies played at the same volume
pink noise is…..
all frequencies played at the same perceived volume
middle A (4) is what frequency
440Hz
period/ time of a wave…..
how long it takes a frequency cycle to complete
wavelength is…..
the distance between 2 corresponding points. Distance travelled by a sound in one period……
phase is…..
the point at which a wave is within its cycle
beat frequencies are…..
a phase interference caused by close frequencies played simultaneously, creates a beating/pulsating sound.
a sine wave is….
a single frequency, with no harmonics. cannot be created naturally, only by tone generators and synths.
a triangle wave is…..
a sine wave, plus odd harmonics
a square wave is…..
a sine wave, with odd harmonics. similar to a triangle wave, but with more, and a different balance of, harmonics
a sawtooth wave is…..
sine waves stacked with odd and even harmonics
any wave shape/ sound can be created by (fourier analysis)….
stacking sine waves at different frequencies and amplitudes, which then form a harmonic series.
harmonics are….
overtones accompanying a fundamental, in direct mathematical relationship to the fundamental.
a higher amplitude makes the perceived frequency…..
flatter/ more linear
equal loudness contour is…..
how we perceive loudness, at different frequencies
the perceived loudness of sound is measured in…..
phons
the fletcher munson curve shows us…..
how our ears perceive different frequencies at different volumes.
what do spl meters do and what does it stand for…..
they are used to measure loudness, and stands for sound pressure level.