ASP FULL SAIL

  1. WHAT ARE THE 3 PRIMARY FACTORS DETERMINING POWER LOSS IN
    SPEAKER CABLE RUNS?
    • cable length
    • cable gauge
    • load
  2. NAME 3 ELEMENTS THAT HAVE THE GREATEST EFFECT ON SYSTEM DESIGN?
    • ROOM
    • SYSTEM
    • OPERATOR
  3. NAME 3 TYPES OF SPEECH INELIGIBILITY MEASUREMENTS?
    • %ALCONS
    • SPEECH TRANSMISSION INDEX
    • CLARITY RATIO
  4. WHAT IS THE NAME USED TO DECRIBE UNITS OF ABSORBTION?
    Sabine
  5. DEFINE CRITICAL DISTANCE.
    the distance from the source where the reverberant and direct sound fileds are equal in level
  6. HOW DOES A TEMPERATURE LAPSE AFFECT SOUND?
    during the day the air temp is warm close to ground. this temp decreases as you increase height. the sound bends toward the sky
  7. HOW DOES A TEMPERATURE INVERSION AFFECT SOUND?
    during night air temp is lower close to ground and increases with height. the sound bends toward the ground
  8. WHAT IS PURPOSE OF “A WEIGHTING” ON AN SPL METER?
    this contour is designed to approximate the ear at the 40 phon level. this weighting is used to measure ambient sound levels
  9. WHAT IS PURPOSE OF “C WEIGHTING” ON AN SPL METER?
    • this contour approximates the ears response at very high sound levels.
    • often used to measure traffic noise
  10. WHAT IS THE RECOMMENDED SPL METER WEIGHTING? WHY?
    • A weighted slow.
    • it focuses attention on the frequencies that sound the loudest and are vital for communication.
  11. NAME SOME COMMONLY USED SPEAKER CABLE CONNECTORS USED BY
    PROFESSIONAL SOUND COMPANIES (MANUFACTURER AND MODEL).
    • nl-4 , 8
    • EP/AP 4,6,8
    • Power
  12. USING A STANDARD WIRE TABLE WE DETERMINE THAT FOR EACH
    300METERS/1000FT OF 10 GAUGE WIRE, WE HAVE 1Ω OF RESISTANCE. HOW
    MUCH RESISTANCE WOULD AN 80METER RUN OF SPEAKER CABLE HAVE?

    2*LENGTH
    ____________ * UNIT Ω = TOTAL Ω
    UNIT LENGTH
    • 2*80
    • _______ * 1Ω = 0.53Ω
    • 300
  13. WHAT DOES THE 5% RULE STATE?
    cable resistance should never exceed 5% of load resistance
  14. WHAT IS “DAMPING FACTOR”?
    a numerical indication of how well an amp can "control" a  loudspeakers cone motion
  15. WHAT WOULD BE THE ELECTRICAL DAMPING FACTOR OF A LOUDSPEAKER
    WITH A DC VOICE COIL RESISTANCE OF 8Ω, AN AMPLIFIER OUTPUT
    IMPEDANCE OF .001Ω, AND A TOTAL CABLE RESISTANCE OF .53Ω?

                     R (VOICE COIL)
    DF=__________________________
            Z (AMP OUT) + R (CABLE)
    • DF=________________      
    •            .001Ω + .53Ω

    df= 15.07Ω
  16. LIVE AUDIO SYSTEMS ARE OPTIMIZED FOR _____________ ________________.
    Voltage Transfer
  17. PROGRAM SOURCES VARY IN ______________, _________________ AND ________________.
    • voltage
    • impedance
    • topology
  18. NAME THE 3 TYPES OF PROGRAM SOURCES.
    • mics
    • instruments
    • playbacks
  19. WHAT IS A MIXER’S MAIN JOB WITH REGARD TO PROGRAM SOURCES?
    scales mic level to line level
  20. WHAT ARE 3 MAIN TYPES OF SIGNAL PROCESSING?
    • filtering
    • delay
    • dynamic
  21. POST MIXER PROCESSING IS MAINLY _____________________ IN NATURE.
    technical (as opposed to artistic)
  22. WHERE DO WE USE “MATCHED” OR “TERMINATED” INTERFACE?
    • wireless antenna systems
    • video systems
    • long transmission lines
  23. IN A ___________ AUDIO CIRCUIT, IT IS BENEFICIAL TO HAVE THE LOAD IMPEDANCE ____ TIMES THE SOURCE IMPEDANCE TO INSURE EFFICIENT ________TRANSFER FROM DEVICE TO DEVICE.
    • bridged
    • 10
    • voltage
  24. WHY CAN’T WE “Y” 2 OUTPUTS TO AN INPUT?
    • outputs will both try to drive each other causing low impedance causing high current to develop
    • outputs are low impedance and meant to drive the higher impedance of the input
  25. LOUDNESS AND POWER RELATE TO THE ________ OF THE SIGNAL.
    RMS
  26. CLIPPING CAUSES ____________ _________________. WHICH CAUSES THE SIGNAL TO SOUND
    BAD.
    Harmonic distortion
  27. WHY IS MONITORING THE PEAKS OF SIGNAL IMPORTANT?
    monitoring peaks can help us avoid distortion
  28. WHY IS MONITORING THE RMS OF SIGNAL IMPORTANT?
    monitoring RMS can help us aviod loudspeaker damage
  29. DEFINE INTEGRATION TIME.
  30. WHAT IS THE DIFFERENCE BETWEEN A “QUASI‐PPM AND A TPPM?
    • A quasi-PPM has a 5-10ms integration timeA quasi-PPM will often read 8-10 dB lower than a TPPM
    • A true PPM (TPPM) has instant ballistics that read out any short term peaks.
  31. WHAT IS THE MAIN DRAWBACK OF USING A PPM?
    • a PPM cannot monitor loudness or RMS
    • Loudness & RMS affect hearing saftey and Potential loudspeaker damage
  32. 0 DBFS CAN BE REFERENCED TO A __________ OR A ___________ WAVE.
    • Square
    • sine
  33. WHEN WOULD A TRUE PEAK PROGRAM METER BE USEFUL?
    when recording to avoid short term peaks that would cause
  34. WHAT IS THE RESPONSE OR INTEGRATION TIME OF A VU METER?
    300 ms
  35. HOW MANY VOLTS DOES 0VU EQUAL?
    1.23v
  36. WHAT IS CREST FACTOR?
    The difference between peak and average signal Crest factor in dB=10log(peak/average)
  37. WHAT IS THE CREST FACTOR OF A SINE WAVE?
    3 db
  38. WHAT IS THE DIFFERENCE BETWEEN AES PINK NOISE AND TRADITIONAL PINK NOISE?
    AES pink is filtered so that it has 6dBCF and traditional pink noise has a crest factor of 10dB
  39. WHAT IS THE CREST FACTOR OF TYPICAL MUSIC?
    20dbcf
  40. what is dynamic range
    peak level - noise floor
  41. what is thermal noise
    • the result of atoms bumping into each other
    • electronic noise
  42. WHY ARE WE FORCED TO DEAL WITH SYSTEM GAIN STRUCTURE?
    • there is no standard noise floor level
    • there is no standard peak input / output level
  43. HOW MANY VOLTS DOES 0 dBU EQUAL?
    • .775 v
    • dervived from old telephone specs based on 600Ω & .001 watt (0dbm)
  44. WHAT DEVICES ARE USED TO ADJUST ATTENUATION WHEN SETTING A SYSTEM’S GAIN STRUCTURE?
    • external pads
    • onboard input / output controls provided they are "BEFORE" the pre-amp
  45. WHAT IS THE PURPOSE OF A SYSTEM LIMITER?
    to act as an early waring device that allows YOU to take measures to protect the system.
  46. WHAT RATIO SETTING IS BEST FOR A SYSTEM LIMITER?
    8:1 or greater
  47. WHAT 3 METHODS ARE USED TO DETERMINE CLIP POINTS IN A SYSTEM?
    • piezo magic
    • onboard indicators
    • oscope
  48. BEFORE PHYSICALLY SETTING GAIN STRUCTURE, WHY DO YOU FIRST RUN SIGNAL THROUGH THE SYSTEM?
    • to check the integrity of the system
    • you must fix grounding / power / driver issues before attempting to cal a systems gain structure
  49. WHY WOULD WE ZERO OUT AN EQ BEFORE ATTEMPTING TO SET GAIN STRUCTURE?
    • any cuts or boosts will affect the EQ output during cal
    • log existing curve before zeroing to prevent possible hurt feelings
  50. CALCULATE THE VOLTAGE SEEN AT AN OUTPUT WITH A METER READING OF 12dBu.
        db
    10___ * ref = volts
        20
  51. WHAT IS AMPLIFIER INPUT SENSITIVITY?
    the amount of voltage req at an amps input to produce full rated output
  52. What are the two components that make up a radio wave?
    • Magnetic ("H" feild)
    • and electrical  ("E" fields)
  53. What is a carrier wave?
    Base unmodulated frequency the TX and RX remain locked to
  54. Name 2 types of modulation
    • Frequency
    • Amplitude
  55. What type of modulation is used for wireless microphone and in-ear monitor systems? Why?
    Frequency modulation has a wider frequency response (50-16k) and better dynamic range. (90+ db)
  56. What 2 types of audio signal processing are used in transmitting and receiving? why?
    • Pre/post emphasis EQ
    • Companding
  57. What does true diversity mean?
    The ability to sample the radio field from 2 or more locations and/or the ability to select/combine the resulting signal.
  58. What diversity design is most common?
    Receiver switching diversity
  59. What is the minimum size for a transmitting or receiving antenna?
    1/4 the size of the wavelength you are transmitting or receiving
  60. What is the best way to maintain maximum efficiency between a transmitting and receiving antenna?
    Line of sight between TX and RX
  61. (T) Name 4 types of commonly used antenna designs
    • Ground plane
    • Whip
    • Yagi
    • Helical
    • logarithmic periodic dipole array (LPDA)
    • circularly polarized
  62. (T) What are the 2 types of antenna distribution and when would we use them?
    • Passive (up to 2)
    • Active (more than 2)
  63. What causes "drop out", "noise up" and "hits"?
    • Obstructions
    • Dead or dying batteries (alkaline)
    • Multi-path effects
  64. What is the purpose of the Squelch Circuit?
    To mute the audio output of the receiver when RF signal level falls below a set threshold.
  65. Which frequency band has its transmitter power limiter to 50mW?
    • VHF (Very High Frequency)
    • 30 to 300mhz
  66. Which frequency band has its transmitter power limiter to 250mW?
    • UHF (Ultra High Frequency)
    • 300 to 3Ghz
  67. Which frequency band is illegal to use as of June 2010?
    UHF 700 to 805 MHZ
  68. Two channels have been allocated in every major city market for wireless use. Where are they located?
    UHF-TV Channel 37
  69. Name some unique benefits ear monitor systems provide
    • Mobility
    • Safer on ears
    • Less stage volume
    • Less chance for feedback
    • Better sounding mix
    • Quick setup and teardown
    • Less bulk on truck
  70. Give some application examples for an in ear monitor system.
    • Theater
    • Broadcast
    • Live performance
    • Studio monitoring
  71. A basic wireless in ear monitor system consist of:
    • Console
    • Multiband peak limiter/processor
    • Transmitter
    • Receiver
    • Ear molds
  72. Why is it important to drive an in ear monitor system transmitter properly?
    • If the input is too low, you will have to operate the receiver volume at too high a level leading to excessive noise.
    • If the input is too high, you will cause overmodulation distortion. There
    • is also a danger of bleed into adjacent radio channels.
  73. Why is a peak limiter necessary at the transmitter input?
    • To prevent hearing damage due to level spike or feedback loop.
    • To enhance the mix.
  74. What band positions typically use a hardwired in ear mix as opposed to a wireless one?
    Stationary performers
  75. What is the first thing you need to do to obtain custom ear molds?
    Go to a hearing aid center or an audiologist and have impressions taken of your ears.
  76. How does an ambient microphone fed into a musician's in ear monitor mix help the musician?
    • it helps the musicians hear crowd response
    • Helps with localization when using isolating molds
    • Allows communication on stage
  77. Explain why a monitor wedge would be used in combination with an in-ear mix.
    Low end supplement
  78. What is multi-band limiting?
    Multi-band limiters allow separate limiter control over multiple frequency bands.
  79. Name some techniques used to enhance the low end of an in ear mix.
    • Bass "shaker"
    • Side fill subs
  80. what is "balanced"
    equal impedance (Z) compared to ground
Author
wolffxfx
ID
204866
Card Set
ASP FULL SAIL
Description
ASP FULL SAIL
Updated