REC 103 Midterm
Card Set Information
REC 103 Midterm
When did Edison create the phonograph?
How does Edison's phonograph work?
inscribed vibrations on tin foil
What was material was later used on the phonograph?
wax cylinders that could be molded and duplicated
Who make the gramophone and when?
Emile Berliner in 1887
How did the gramophone work?
inscribed onto a round flat shellac-coated disc
What did the gramophone eventually lead to?
vinyl LP records
What benefit did the gramophone have over the phonograph?
longer play times
When was electronic amplification started?
What did electronic amplification do for the industry?
improved volume and fidelity
How did the microphone improve the industry?
to balance the performance being recorded; multiple mics could be used for more balance
When and where was magnetic recording started?
1930's, Germany (Hitler recording speeches and then playing them on radio)
What material was first used for magnetic recording, and then what was it replaced with?
first with a wire/metal bands; replaced by PVC recording tape
Les Paul's contributions to recording (and dates)
Sound on sound
Who developed the first 8-track recorder?
What are the track counts you could have on 2" tape?
4, 8, 16, and 24
When did stereo replace mono? When was the cassette tape developed?
Other 1960's recording developments:
"Walkman" personal stereo
When and who announced the CD in development?
1979 by Philips
When was the CD launchd?
What developments happened in the digital revolution?
tape-based digital recording
software-based recording introduced
Internet and beyond:
internet technology, world wide web
revolutionized all media production (MP3, MP4)
Parts of a Pro Studio:
up-to-date equipment, expertly maintained
comfortable/pro work environment
optimized control/mix room
Recording signal path:
transducer -> amplification -> recording system
What is a transducer?
any component that converts one form of energy to another corresponding form
Recording signal path: Tranducer
Recording signal path: Amplification
Recording signal path: Recording system
hard drive-based computer system (AKA DAW)
What is sound?
atmospheric disruption in the air
What is audio?
the electronic signal of sound
Studio signal path:
tracking room -> control room -> machine room
Studio signal path: Tracking room
panels with XLR sockets
window that looks into the next room
Studio signal path: Control room
console or HUI
engineer at console
equipment rack (also producer's desk w/ couch behind it
soffit (party speakers)
monitor screen for edit/mix
Studio signal path: Machine room
rack of protools
keyboard and mouse
maybe a rack of modulars
analogue tape machine
multitrack panel going to the patchbay
What company introduced the XLR cable and what was its original purpose?
Canon; camera audio
What are XLR cables now used for?
balanced audio connection, timecode and sync in video
What does the AES/EBU protocol allow?
lets 2 channels of digital down 1 cable
What is DI and what does it do?
DI= Direct Injection; takes high impedance and makes it low impedance
What is the metal part at the end of an XLR cable called?
What is underneath the metal part at the end of an XLR?
XLR pin designations:
: signal +
: signal -
Male and Female XLR pinouts: (read clockwise)
: 2(+), 1(shield), 3(-)
: 1(shield), 2(+), 3(-)
Which phone plug is balance and which isn't?
What is "Tiny Telephone" used for in the industry?
exclusively for patch cables
RCA: (Radio Corporation of America)
usually used for consumer audio+video; unbalanced
SPDIF: (Sony/Philips Digital Interface)
consumer version of AES/EBU for RCA; sometimes call "coaxial" for 2 channels down one cable
sends modulated digital data down a fiber optic cable; multichannel digital I/O
multi-pin multi-channel connectors for analogue
for Elco, have different sizes and configs; digital+analogue
digital interface to computer connections
MIDI standard cable; introduced at NAMM in 1983 so that an electronic instrument could talk to each other; also European consumer audio standard
1st law of electrostatics:
like charges repel, unlike charges attract
What is a positive and negative ion?
: lacking electrons
: excess electrons
Why are metals so good at conducting electricity?
their atomic structure allows the electricity to flow in exchange for electrons
What does DC mean for electricity?
electricity flows in one direction
What does AC mean for electricity?
electricity flows in both directions
Which is more efficient with long cables, DC or AC?
what is its measurement?
quantity of electrons passing a point; Ampere
What is 1 ampere equivalent to?
6.28 x 10
electrons in 1 second = 1 ampere
electrical pressure/force, "potential"
what is it measured in?
"work" performed by an electrical current; watts
what is it measured in?
resist current in a conductor or circuit; ohms
what does each part of the water tank model represent?
water in tank= voltage (potential)
water coming out of faucet= current
paddle wheel turning= work
What is a circuit?
any arrangement of components that lets an electrical current to flow
current that must pass through one component to reach the next
2 or more components are connects so a current flows through one component without flowing through another
What is a wave?
periodic fluctuation in current or voltage
What does a positive (above line) sine wave represent?
What does a positive and negative sine wave represent:
What does a square wave sound like and what makes it square?
it's a distortion sound; it's a clipped sine wave
What is a square wave useful for?
can be used for timecode since it's either all up or all down (1 and 0 in binary code)
(maybe on board) point in a circuit where there is 0 voltage
connects earth ground to interior component using 3rd prong on power cable
metal rod or pipe in the ground connected to electrical system
usually metal like copper; stranded or solid core
Switches - pole:
# of connections in switch
Switches - throw:
how many connections can be made
electromagnetic switch; current goes through coil and magnetizes new contacts
converts sound wave variations into electrical currents
movement of diaphragm moves coil in a magnetic field
alters the distance between two metal plates varying the capacitance
works in reverse of dynamic mic
limits current; controls current to an appropriate level for the component behind it
stores electrons (a charge); smoothes and conditions current; can also split frequencies
if you have 2 values, you may calculate the 3rd
Ohm's law equation:
Voltage (V) = Current (I) x Resistance (R)
Kilo = 1000
Mega = 1,000,000
Milli = .001
How does current flow?
current flows through a wire by the exchange of electrons; positive ion in conductor attracts extra electrons in the current's negative ions
How to read resistor bands:
: first digit
: second digit
What is to be assumed if there is no fourth band on a resistor?
assume ±20% tolerance