Unit 2 Flashcards
Define analog recording
a type of recorded signal that produces a wave similar to that of the original wave.
Define transduction
the process of changing one form of energy to another
Define phonograph
a device created by Thomas Edison using a microphone, a needle, and a rotating foil cylinder to record sound
Define magnetic tape
mylar tape with a thin coating of magnetic particles; each is a tiny magnet and is arranged in random fashion
Define digital recording
a type of recorded signal that is comprised of samples of original sound
Define bit
on or off state in computer language. Each audio sample is made of a string of these.
Define sample rate
how many times per second the signal is sampled
Who invented the phonograph in 1877
Thomas Edison
What were nickelodians?
machines that you could put a nickel in to and hear a song of your choice
Define microphone
a transducer that converts a sound wave into an electrical wave that can then be amplified and broadcast
Which microphone type requires an external power source
condensor mic
What is the power source for a condensor mic called?
phantom power
What are the three types of microphones we talked about in class?
dynamic, condensor, ribbon
What are the pros and cons of dynamic mics?
pros:
inexpensive, very durable, performs well in difficult sound conditions
cons:
less response to higher frequency sounds
What are the pros and cons of ribbon mics?
pros:
very good high frequency response, warm rich tones, excellent sensitivity
cons:
very delicate and easily damaged, sensitive to popping noises from Bs and Ps
What are the pros and cons of condenser mics?
pros:
high sensitivity and extended frequency response, reasonably durable
cons:
needs external power supply, susceptible to moisture damage
Which mic is also known as the “moving coil mic”
dynamic
What is an omnidirectional mic?
a mic that picks up sound well from all directions
What is a bi-directional mic?
a mic that picks up sound from front and rear equally, but rejects sounds from the sides
What is a cardiod mic?
also known as unidirectional, only picks up sound from the front. It is known as cardiod because the shape of its pickup pattern looks like a heart.
What is a shotgun mic?
a long mic with a long focused pick up range
What is a windscreen?
foam covering for microphones to help prevent unwanted noises
How close together should mics be placed?
Space mics about three times the the source distance apart
What are imaging and depth when referring to recording?
imaging: the apparent placement of certain sounds from left to right
depth: the apparent placement of certain sounds from front to back
What are the four components of speakers?
tweeter: produces high frequencies
woofer: produces mid frequencies
sub-woofer: produces low frequencies
crossover: sends frequencies to the proper drivers
What does SPL stand for?
sound pressure level
Define sensitivity
amount of sound a speaker can produce from a given input level
What is phasing?
when one sound and an inverse sound cancel each other out
What is the name for the process of over-dubbing during a multi-track recording?
punching in
What is the name for the unwanted sound that comes from wires?
hum
What is the name for the average common audio plug?
phone connector
RCA cables are also known as what?
phono cables
What unit is impedance measured in?
ohms
Amplitude is measured in what?
decibels
What is panning?
audio spread across a left to right spectrum
Define frequency response
how well certain devices respond to different frequencies
Which kind of mic has two bars inside with an electric charge between?
condensor
In 1873, who published the theory on electromagnetic waves?
James Maxwell
Who used experiments to send and detect audio waves.
Heinrich Hertz
Who invented wireless telegraphy?
Marconi
Who made the first radio broadcast?
Reginald Fessenden
Who invented the audion tube?
Lee De Forest
What does RCA stand for?
Radio Corporation of America
Who saw wireless technology as a form of entertainment and became the first DJ?
Frank Conrad
What was the first radio station?
KDKA Pittsburgh, Pennsylvania
What event happened in 1940 that threatened the very existence of radio?
the invention of television
What is pirate radio?
People hijack radio waves and broadcast their own signal
What do AM and FM stand for?
Amplitude Modulation
Frequency Modulation
What is the default sample rate for CD quality?
44.1 khz / 16 bit
What is ERP?
abbreviation for the three playheads in analog recording (Erase, Record, Play)
What were potential problems with using tape for recording?
poor frequency response, slow and fast variations due to dirty tape path (known as wow and flutter), crosstalk (signals from different tracks getting mixed), and hiss (noise generated by random particles in the tape)
What advantages did analog recording have over digital?
gentler and warmer sound, captured entire sound rather than just a sample
Every digital audio sample is made up of a string of on or off states in computer language called what?
bits
What is the technical term for air molecules being pulled apart?
rarefaction
What is amplitude?
the height of the wave, determines how loud the sound is
Define cycle
one complete vibration from normal to high to low to normal
Define frequency
the number of cycles per second
What is wavelength?
physical distance between peaks of waves
Define timbre
the specific shape of the wave that makes it sound different from other noises
Define attack and decay
Attack: how long a sound takes to get from silence to maximum volume
Decay: how long it takes to get from maximum to midrange
Define sustain
how long a sound holds
Define release
how long it takes for a sound to fade to silence after sustain
Define phase shift
when two identical waves are slightly delayed from each other and are out of phase
What is a signal to noise ratio?
the amount of difference in volume (dB) between the audio signal at optimal level and the noise made by the equipment
What are the raw audio formats for Mac and Windows?
Mac: AIFF
Windows: WAV
Define bit depth
number of bits allocated to each sample
