Rec 103 Final

  1. When did Edison create the phonograph?
  2. How does Edison's phonograph work?
    inscribed vibrations on tin foil
  3. What was material was later used on the phonograph?
    wax cylinders that could be molded and duplicated
  4. Who make the gramophone and when?
    Emile Berliner in 1887
  5. How did the gramophone work?
    inscribed onto a round flat shellac-coated disc
  6. When was electronic amplification started?
  7. When and where was magnetic recording started?
    1930's, Germany (Hitler recording speeches and then playing them on radio)
  8. 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
  9. Les Paul's contributions to recording (and dates)
    • Sound on sound: 1946
    • Multitrack recording: 1950s
  10. Who developed the first 8-track recorder?
  11. When did stereo replace mono?  When was the cassette tape developed?
  12. Other 1960's recording developments:
    • quad recording
    • "Walkman" personal stereo
  13. When and who announced the CD in development?
    1979 by Philips
  14. When was the CD launchd?
  15. What developments happened in the digital revolution?
    • CD launched
    • digital recording
    • MIDI introduced
    • tape-based digital recording
    • software-based recording introduced
  16. Internet and beyond:
    • internet technology, world wide web
    • revolutionized all media production (MP3, MP4)
    • computer-based workstation
  17. Parts of a Pro Studio:
    • Pro staff
    • up-to-date equipment, expertly maintained
    • comfortable/pro work environment
    • optimized acoustics
    • optimized control/mix room
  18. Recording signal path:
    transducer -> amplification -> recording system
  19. What is a transducer?
    any component that converts one form of energy to another corresponding form
  20. Recording signal path: Tranducer
    • microphone
    • pickup
    • phonograph pickup
  21. Recording signal path: Amplification
    • console/mixer
    • interface
    • preamp/live amp
  22. Recording signal path: Recording system
    • analogue tape
    • tape-based digital 
    • hard drive-based computer system (AKA DAW)
  23. What is sound?
    atmospheric disruption in the air
  24. What is audio?
    the electronic signal of sound
  25. Studio signal path:
    tracking room -> control room -> machine room
  26. Studio signal path: Tracking room
    • mic+stands
    • amps
    • artist
    • panels with XLR sockets
    • window that looks into the next room
  27. Studio signal path: Control room
    • console or HUI
    • engineer at console
    • equipment rack (also producer's desk w/ couch behind it
    • near-field monitors
    • soffit (party speakers) 
    • patchbay
    • monitor screen for edit/mix
  28. Studio signal path: Machine room
    • rack of protools
    • keyboard and mouse
    • monitor screen
    • maybe a rack of modulars
    • analogue tape machine 
    • multitrack panel going to the patchbay
  29. What company introduced the XLR cable and what was its original purpose?
    Canon; camera audio
  30. What are XLR cables now used for?
    balanced audio connection, timecode and sync in video
  31. What does the AES/EBU protocol allow?
    lets 2 channels of digital down 1 cable
  32. What is DI and what does it do?
    DI= Direct Injection; takes high impedance and makes it low impedance
  33. What is the metal part at the end of an XLR cable called?
  34. What is underneath the metal part at the end of an XLR?
    braided shield
  35. XLR pin designations:
    • 1: shield
    • 2: signal +
    • 3: signal -
  36. Male and Female XLR pinouts: (read clockwise)
    • Male: 2(+), 1(shield), 3(-)
    • Female: 1(shield), 2(+), 3(-)
  37. Which phone plug is balance and which isn't?
    • TRS: balanced
    • TS: unbalanced
  38. What is "Tiny Telephone" used for in the industry?
    exclusively for patch cables
  39. RCA: (Radio Corporation of America)
    usually used for consumer audio+video; unbalanced
  40. SPDIF: (Sony/Philips Digital Interface)
    consumer version of AES/EBU for RCA; sometimes call "coaxial" for 2 channels down one cable
  41. Fiber Optics:
    sends modulated digital data down a fiber optic cable; multichannel digital I/O
  42. Elco:
    multi-pin multi-channel connectors for analogue
  43. D-Sub:
    for Elco, have different sizes and configs; digital+analogue
  44. USB/Firewire:
    digital interface to computer connections
  45. 5-pin DIN:
    MIDI standard cable; introduced at NAMM in 1983 so that an electronic instrument could talk to each other; also European consumer audio standard
  46. 1st law of electrostatics:
    like charges repel, unlike charges attract
  47. What is a positive and negative ion?
    • positive: lacking electrons
    • negative: excess electrons
  48. Good conductors:
    • gold
    • copper
    • silver
    • iron
    • aluminium
  49. Why are metals so good at conducting electricity?
    their atomic structure allows the electricity to flow in exchange for electrons
  50. Insulators:
    • rubber
    • wood
    • plastic
    • nylon
    • cloth
    • glass
  51. What does DC mean for electricity?
    electricity flows in one direction
  52. What does AC mean for electricity?
    electricity flows in both directions
  53. Which is more efficient with long cables, DC or AC?
  54. Current (I):
    what is its measurement?
    quantity of electrons passing a point; Ampere
  55. What is 1 ampere equivalent to?
    6.28 x 1018 electrons in 1 second = 1 ampere
  56. Voltage (V):
    electrical pressure/force, "potential"
  57. Power (P):
    what is it measured in?
    "work" performed by an electrical current; watts
  58. Resistance (R):
    what is it measured in?
    resist current in a conductor or circuit; ohms
  59. what does each part of the water tank model represent?
    • water in tank= voltage (potential)
    • faucet= resistance
    • water coming out of faucet= current
    • paddle wheel turning= work
  60. What is a circuit?
    any arrangement of components that lets an electrical current to flow
  61. Series circuit:
    current that must pass through one component to reach the next
  62. Parallel circuit:
    2 or more components are connects so a current flows through one component without flowing through another
  63. What is a wave?
    periodic fluctuation in current or voltage
  64. 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)
  65. Circuit ground:
    (maybe on board) point in a circuit where there is 0 voltage
  66. Chassis ground:
    connects earth ground to interior component using 3rd prong on power cable
  67. Earth ground:
    metal rod or pipe in the ground connected to electrical system
  68. Wire/cable:
    usually metal like copper; stranded or solid core
  69. Switches - pole:
    # of connections in switch (like how many things that get turned "on")
  70. Switches - throw:
    how many connections can be made at once
  71. Relay:
    electromagnetic switch; current goes through coil and magnetizes new contacts
  72. Microphone:
    converts sound wave variations into electrical currents
  73. Dynamic mic:
    coil of wire vibrates in a magnetic field, .35mil mylar is attached to coil and vibrates with it; vibrations sent down wires to cable
  74. Ribbon mic:
    diaphragm of VERY THIN ALUMINUM suspended in strong magnetic field; vibrations of ribbon produces its own current, step-up transformer boosts output and fixes impedance
  75. What else is included on the pre-amp board in a condenser mic?
    low freq. roll off and attenuation pad (decrease voltage and avoid distortion)
  76. Condenser mic:
    fixed back plate with moveable plate (diaphragm) from capacitor; voltage potential change is the output
  77. Speaker:
    works in reverse of dynamic mic
  78. Resistor:
    limits current; controls current to an appropriate level for the component behind it
  79. Capacitor:
    stores electrons (a charge); smoothes and conditions current; can also split frequencies
  80. Ohm's law:
    if you have 2 values, you may calculate the 3rd
  81. Ohm's law equation:
    Voltage (V) = Current (I) x Resistance (R)
  82. Kilo = 
    Mega = 
    Milli =
    • Kilo = 1000
    • Mega = 1,000,000
    • Milli = .001
  83. 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
  84. How to read resistor bands:
    • first band: first digit
    • second band: second digit
    • third band: multiplier
    • fourth band: tolerance
  85. What is to be assumed if there is no fourth band on a resistor?
    assume ±20% tolerance
  86. Transient:
    brief, fast change in sound pressure
  87. Equalization:
    selective frequency manipulation
  88. Peaking EQ:
    boost/cut around a century frequency; bandwidth and frequency can be selected
  89. Bandwidth:
    how much of either side of center is affected
  90. What does "dynamics" refer to?
    altering the natural range of signal (0-140db in nature); often used to reduce the range of volume
  91. Time Based Effects:
    at the core of all the time based effects is delay
  92. Parametric EQ:
    can select freq., boost/cut, and bandwidth independently usually with rotary pots
  93. Shelving EQ:
    typically high or low freq., pick a freq. and boost/cut all freq. above/below selected freq.
  94. Notching EQ:
    using the thinnest bandwidth possible to boost/cut a certain frequency
  95. Filters:
    • like shelving, but it drops to infinity
    • *They are passive, so they don't add to noise
  96. Filter set:
    pick out very narrow bands and infinitely drop them
  97. Comb Filter:
    when you combine delayed signal with a varying delay of the same signal, phase cancelation and reinforcement takes place (delays need to be very short)
  98. Saturation:
    when input signal is too much for amp and distorts
  99. Average signal level:
    overall signal level
  100. System/ambient noise:
    signal is too low and is buried in the mix
  101. Dynamic Envelope:
    • Attack
    • Decay
    • Sustain
    • Release
  102. Peak limiting:
    control only peak voltages to protect against saturation (distortion); anything surpassing threshold is gain reduced an equal amount that it goes above
  103. Compression:
    reduces overall dynamic range (allows us to increase gain back up to original level); used to even out an inconsistent performance to increase its presence in the mix
  104. Signal Gate:
    "electronic switch" that allow signal ONLY of sufficient amplitude through the circuit; can be used to cut out amp noise, mic bleed, or triggering things
  105. Threshold:
    voltage level at which gain reduction begins; a low threshold means it works sooner
  106. High Threshold, low ratio =
    minimal gain reduction
  107. Ratio:
    • when the signal goes above the threshold, the ratio tells the device how much gain reduction you want on the signal
    • ex: 4:1 means for every 4dB over the threshold level, 1dB will come out over the threshold level
  108. Attack:
    in milliseconds, determines how long after the signal surpasses the threshold gain reduction begins (how quickly gain reduction starts)
  109. Release:
    in milliseconds, adjust how long after the signal falls below threshold does gain reduction continue
  110. Knee:
    how hard the gain reduction is applied, helps make it sound less compressed
  111. Make-up gain:
    helps make up the gain you lose from gain reduction
  112. Gates - Hold:
    allows gat to stay open after signal has dropped below threshold
  113. Gates - Range:
    feather the undated signal into the gated signal
  114. Sample and hold circuit:
    takes snapshots of analogue signal's voltages
  115. CD audio sample rate:
    44.1kHz, means it samples the voltage 44,100 times/second
  116. Quantization:
    assign digital value (0 or 1) in bits to each sample
  117. CD audio bit depth:
    16 bits resolution
  118. Typical sample rates:
    44.1, 48, 88.2, 96
  119. Typical bit depths:
    16, 20, 24, 32
  120. What happens when one sound is slightly louder than another in the same frequency?
    they are canceled out (masking)
  121. Nyquist theorem:
    to get an accurate digital recording, you must use a sample rate at least 2x that of the highest frequency to capture
  122. Anti-aliasing filtering:
    low pass filter (high cut), ends at about 22.05 kHz (when Nyquist is applied, you get the 44.1kHz sample rate)
  123. Dither:
    low level white/pink noise inserted to make up for when early digital systems would cut off signal when it got really low
  124. Error correction:
    repair/replace any missing or corrupted data
  125. Modulation:
    repackages the data for computer use (bytes)
  126. Multiplexing:
    converting multiple tracks at once by adding extra data to tell the receiving end what goes where
  127. A/D conversion:
    • Line Amp
    • (dither)
    • Anti-aliasing
    • Error Correction
    • Modulation
    • Multiplexing
  128. How Analogue Recording works
    two magnets are each wrapped in wire (head) without touching each other, they create a magnetic flux; signal goes to record electronics, and then to console
  129. Magnetic flux:
    magnetic field that magnetizes oxide particles on tape (particles don't move, the poles change)
  130. What needs to be constantly calibrated on analogue machines:
    • operating levels
    • record/playback EQ
    • bias level
  131. Bias Level:
    sine wave constantly on by the bias oscillator at 75-150kHz
  132. How often does the bias level need to be set?
    for every new project and every new reel of tape
  133. What happens to the magnetic flux without the bias level?
    the magnetic flux won't be strong enough to magnetize the tape
  134. Operating Level:
    how high of a signal to send the tape
  135. Nanoweber:
    nW/m is how much change of magnetic flux
  136. Why would you use a higher dB setting for tape?
    analogue tape moderately compresses the signal, so higher dB is used to make up for it
  137. MRL tape:
    Magnetic Resonance Labs; series of sine wave tones from 20Hz to 20kHz
  138. Sync Mode:
    borrow the record head to playback or punch in
Card Set
Rec 103 Final
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