Shared Flashcard Set

Details

Advanced Show Production Systems
ASP Final
133
Engineering
Undergraduate 4
04/18/2013

Additional Engineering Flashcards

 


 

Cards

Term
•WHAT ARE THE 3 PRIMARY FACTORS DETERMINING POWER LOSS IN SPEAKER CABLE RUNS?
Definition

• Length

• Load

• Gauge

Term
•NAME 3 ELEMENTS THAT HAVE THE GREATEST EFFECT ON SYSTEM DESIGN?
Definition
• Room
• System
• Operator
Term
•NAME 3 TYPES OF SPEECH INTELLIGIBILITY MEASUREMENTS?
Definition

1. %ALcons- Articulation Loss of Consonants

2. Speech Transmission Index

3. Clarity Ratio-Energy Time Curve

C50-Speech

C80-Concert

Initial Time Delay Gap

Term
•WHAT IS THE NAME USED TO DESCRIBE UNITS OF ABSORPTION?
Definition
Sabine
Term
•DEFINE CRITICAL DISTANCE.
Definition

The distance from the source where the reverberant and direct sound field are equal in level.

Term
•HOW DOES A TEMPERATURE LAPSE AFFECT SOUND?
Definition
Sound bends toward the colder air.

The sound ray paths curve upward. During the day, the air temperature is warm close to the ground. This temperature decreases as you increase height. The sound bends toward the sky.
Term
•HOW DOES A TEMPERATURE INVERSION AFFECT SOUND?
Definition
Sound bends toward the colder air.

During the night. The air temperature is lower closest to the ground and increases with height. The sound bends toward the ground.
Term
•WHAT IS PURPOSE OF “A WEIGHTING” ON AN SPL METER?
Definition
This contour is designed to approximate the ear at the 40phon level. This weighting is used to measure ambient sound levels.
Term
•WHAT IS PURPOSE OF “C WEIGHTING” ON AN SPL METER?
Definition
•This contour approximates the ear’s response at very high sound levels.

•Often used to measure traffic noise.
Term
•WHAT IS THE RECOMMENDED SPL METER WEIGHTING? WHY?
Definition
“A” Weighted slow correlates with most standard exposure limitation charts.

•"A" Weighted slow is also recommended because it focuses attention on the frequencies that sound the loudest and are vital for communication.
Term
•NAME SOME COMMONLY USED SPEAKER CABLE CONNECTORS USED BY PROFESSIONAL SOUND COMPANIES (MANUFACTURER AND MODEL).
Definition
• NL-4,8
• EP/AP 4,6,8
• POWER
Term

•USING A STANDARD WIRE TABLE WE DETERMINE THAT FOR EACH 300METERS/1000FT OF 10 GAUGE WIRE, WE HAVE IW OF RESISTANCE. HOW MUCH RESISTANCE WOULD AN 80METER RUN OF SPEAKER CABLE HAVE?

[image]

Definition
0.53Ω
Term
•WHAT DOES THE 5% RULE STATE?
Definition
CABLE RESISTANCE SHOULD NEVER EXCEED 5% OF LOAD RESISTANCE.
Term
•WHAT IS “DAMPING FACTOR”?
Definition
A numerical indication of how well an amplifier can “control” a loudspeaker’s cone motion. FOLLOW THE 5% RULE!
Term

•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?

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Definition
Term
LIVE AUDIO SYSTEMS ARE OPTIMIZED FOR __________ ___________.
Definition
Voltage Transfer
Term
PROGRAM SOURCES VARY IN __________, __________&__________.
Definition
Voltage, Impedance & Topology (Connectors)
Term
NAME THE 3 TYPES OF PROGRAM SOURCES.
Definition
Microphone, Instruments, Playback
Term
WHAT IS A MIXER’S MAIN JOB WITH REGARD TO PROGRAM SOURCES?
Definition
To scale mic level signals to line level (+4dBu)
Term
WHAT ARE 3 MAIN TYPES OF SIGNAL PROCESSING?
Definition
Filtering, Delay, Dynamics
Term
POST MIXER PROCESSING IS MAINLY ________________ IN NATURE.
Definition
Technical (as opposed to Artistic)
Term
WHERE DO WE USE “MATCHED” OR “TERMINATED” INTERFACE?
Definition
Video, Wireless Antenna Systems & Long Transmissions
Term
IN A ___________ AUDIO CIRCUIT, IT IS BENEFICIAL TO HAVE THE LOAD IMPEDANCE ____TIMES THE SOURCE IMPEDANCE TO INSURE EFFICIENT ________TRANSFER FROM DEVICE TO DEVICE.
Definition
Bridged, 10, Voltage
Term
WHY CAN’T WE “Y” 2 OUTPUTS TO AN INPUT?
Definition
•Outputs will both try to drive each others low impedance causing high current to develop.
•Outputs are low impedance and meant to drive the higher impedance of the input.
Term
LOUDNESS AND POWER RELATE TO THE _____ OF THE SIGNAL.
Definition
RMS
Term
CLIPPING CAUSES _________ __________ WHICH CAUSES THE SIGNAL TO SOUND BAD.
Definition
Harmonic Distortion
Term
WHY IS MONITORING THE PEAKS OF SIGNAL IMPORTANT?
Definition
Monitoring peaks can help us avoid loudspeaker damage.
Term
WHY IS MONITORING THE RMS OF SIGNAL IMPORTANT?
Definition
Monitoring RMS can help us avoid loudspeaker damage.
Term
DEFINE METER INTEGRATION TIME.
Definition
The time it takes for a meter to respond to a signal.
AKA Meter Ballistics.
Term
WHAT IS THE DIFFERENCE BETWEEN A “QUASI” AND A “TRUE” PPM?
Definition
•A quasi-ppm has a 5-10ms integration time causing it to not display short-term peaks. A quasi-PPM will often read 8-10dB lower then a TPPM.
•True ppm (TPPM) has instant ballistics that read out any short term peaks. TPPMs are often used in the recording environment to avoid any instance of distortion.
Term
WHAT IS THE MAIN DRAWBACK OF USING A PPM?
Definition
•A PPM cannot monitor loudness or RMS.
•Loudness and RMS affect hearing safety and potential loudspeaker damage.
Term
0 DBFS CAN BE REFERENCED TO A ______ OR A ______ WAVE.
Definition
Square or a Sine
Term
WHEN WOULD A TRUE PEAK PROGRAM METER (TPPM) BE USEFUL?
Definition
•When recording to avoid short term peaks that would cause unwanted harmonic distortion.
Term
WHAT IS THE RESPONSE OR INTEGRATION TIME OF A VU METER?
Definition
300ms
Term
HOW MANY VOLTS DOES 0VU EQUAL?
Definition
1.23V
Term
WHAT IS CREST FACTOR?
Definition
•The difference between peak and average signal.
•Crest factor in dB=10log(peak/average)
•Heating capacity of the signal
“Area under the curve”
Term
WHAT IS THE CREST FACTOR OF A SINE WAVE?
Definition
3dB
Term
WHAT IS THE DIFFERENCE BETWEEN AES PINK NOISE AND TRADITIONAL PINK NOISE?
Definition
•AES pink is filtered so that it has 6dBCF.
•Traditional pink noise has a crest factor of 10dB.
•All pink noise is filtered white noise and has equal energy per octave.
Term
WHAT IS THE CREST FACTOR OF TYPICAL MUSIC?
Definition
20 dBCF
Term
•WHAT IS DYNAMIC RANGE?
Definition
Peak level – Noise Floor.
Term
•WHAT IS THERMAL NOISE?
Definition
•The result of atoms bumping into each other.
•Electronic Noise.
Term
•WHY ARE WE FORCED TO DEAL WITH SYSTEM GAIN STRUCTURE?
Definition
•There is no standard noise floor level.
•There is no standard peak input/output level.
Term
•HOW MANY VOLTS DOES 0 dBU EQUAL?
Definition
.775V
Derived from old telephone specs based on 600Ω and .001 watt (0dBm) “U” stands for undetermined.
Term
•WHAT DEVICES ARE USED TO ADJUST ATTENUATION WHEN SETTING A
SYSTEM’S GAIN STRUCTURE?
Definition
•External pads
•Onboard input/output controls provided they are “before” the pre-amp.
Term
•WHAT IS THE PURPOSE OF A SYSTEM LIMITER?
Definition
To act as an early warning device that allows you to take measures to protect the system.
Term
•WHAT RATIO SETTING IS BEST FOR A SYSTEM LIMITER?
Definition
8:1 or greater.
Term
•WHAT 3 METHODS ARE USED TO DETERMINE CLIP POINTS IN A SYSTEM?
Definition
•Piezo magic,
•Onboard indicators,
•Oscilloscope
Term
•BEFORE PHYSICALLY SETTING GAIN STRUCTURE, WHY DO YOU FIRST RUN SIGNAL THROUGH THE SYSTEM?
Definition
•To check the integrity of the system.
•You must fix grounding, power, and driver issues before attempting to calibrate a system’s gain structure.
Term
•WHY WOULD WE ZERO OUT AN EQ BEFORE ATTEMPTING TO SET GAIN STRUCTURE?
Definition
•Any cuts or boosts will affect the EQ output during calibration.
•Log the existing curve before zeroing to prevent possible hurt feelings.
Term
•CALCULATE THE VOLTAGE SEEN AT AN OUTPUT WITH A METER READING OF 12dBu.
Definition
10ˆdb/20 x Reference Volts = Volts 3.08V
Term
•WHAT IS AMPLIFIER INPUT SENSITIVITY?
Definition
The amount of voltage required at an amplifier's input to produce full rated output.
Term
•WHAT ARE THE TWO COMPONENTS THAT MAKE UP A RADIO WAVE?
Definition
Magnetic field (“H” Field), Electric field (“E” Field): Determines polarization.
Term
•WHAT IS A CARRIER WAVE?
Definition
Base unmodulated frequency the TX and RX remain locked to.
Term
•NAME TWO TYPES OF MODULATION?
Definition
Frequency & Amplitude
Term
•WHAT TYPE OF MODULATION IS USED FOR WIRELESS MICROPHONE AND IN EAR–MONITOR SYSTEMS? WHY?
Definition
Frequency modulation because it has a wider frequency response (50-16kHz) and better dynamic range (90+ dB).
Term
•WHAT TWO TYPES OF AUDIO SIGNAL PROCESSING ARE USED IN
TRANSMITTING AND RECEIVING? WHY?
Definition
•Pre/Post emphasis EQ
•Companding
Term
•WHAT DOES TRUE DIVERSITY MEAN?
Definition
The ability to sample the radio field from 2 or more location and/or the ability to select/combine the resulting signal.
Term
•WHAT DIVERSITY DESIGN IS MOST COMMON?
Definition
Receiver switching diversity.
Term
•WHAT IS THE MINIMUM SIZE FOR A TRANSMITTING OR RECEIVING ANTENNA?
Definition
¼ the size of the wavelength you are transmitting or receiving.
Term
•WHAT IS THE BEST WAY TO MAINTAIN MAXIMUM EFFICIENCY BETWEEN A TRANSMITTING AND RECEIVING ANTENNA?
Definition
Line of sight between TX and RX.
Term
•NAME 4 TYPES OF COMMONLY USED ANTENNA DESIGNS.
Definition
•Ground Plane
•Whip
•Yagi
•Logarithmic periodic dipole array (LPDA)
•Helical
•Circularly Polarized
Term
•WHAT ARE THE TWO TYPES OF ANTENNA DISTRIBUTION AND WHEN WOULD WE USE THEM?
Definition
Passive (up to 2), Active (more than 2).
Term
•WHAT CAUSES “DROP OUT”, “NOISE UP” AND “HITS”?
Definition
•Obstructions
•Dead or dying Batteries
•Multi-path Effects
Term
•WHAT IS THE PURPOSE OF THE SQUELCH CIRCUIT?
Definition
To mute the audio output of the receiver when RF signal level falls below a set threshold.
Term
•WHICH FREQUENCY BAND HAS its TRANSMITTER POWER LIMITER TO 50mW?
Definition
VHF (Very High Frequency)
Term
•WHICH FREQUENCY BAND HAS its TRANSMITTER POWER LIMITER TO 250mW?
Definition
UHF (Ultra High Frequency) 300-3GHz.
Term
•WHICH FREQUENCY BAND IS ILLEGAL TO USE AS OF JUNE 2010?
Definition
UHF 700 to 805 MHz.
Term
•TWO CHANNELS HAVE BEEN ALLOCATED IN EVERY MAJOR CITY MARKET FOR WIRELESS USE. WHERE ARE THEY LOCATED?
Definition
UHF – TV Channel 37: the first open channel that is above and the first open channel that is below.
Term
Name the three parts of the fiber optic cable.
Definition
Core, Cladding, Coating
Term
What is the difference between multimode and single mode fiber?
Definition
One has short distance and lower bandwidth. The other has long distance and unlimited bandwidth.
Term
What is the difference between tight and loose buffer cable?
Definition
One is light weight, easy to terminate, and for indoor use.
The other has greater resistance to temperature changes, used outdoors, and harder to terminate.
Term
Name the four advantages of using fiber over copper cables.
Definition
Difficult to tap, Immune to EMI, Longer Distances, Greater Information Capacity, No crosstalk.
Term
Name two methods used to splice fiber cables.
Definition
Fusion and Mechanical
Term
What are the two most common connectors used for termination of fiber?
Definition
SC (square), ST (round)
Term
Name three fiber optic light sources used in fiber optics.
Definition
LED, VCSEL, Laser Diode
Term
What does VCSEL stand for?
Definition
Vertical Cavity Surface Emitting Laser
Term
Name some unique benefits ear monitors provide.
Definition
Mobility, safer on ears, stage sight lines, less stage volume, less chance for feedback, better sounding mix, quick set-up and strike, less bulk.
Term
Give some application examples of an in ear monitor system.
Definition
Theater, broadcast, live performance, studio monitoring.
Term
A basic wireless in-ear monitor system consists of…
Definition
Console → multi-band peak limiter/compressor → transmitter → receiver → ear molds.
Term
Why is it important to drive an in-ear monitor system transmitter properly?
Definition
•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 over-modulation distortion. There is also a danger of bleed into adjacent radio channels.
Term
Why is a multi-band peak limiter necessary at the transmitter input?
Definition
To prevent hearing damage due to a level spike or feedback loop, and to enhance the mix.
Term
What bank positions typically use hardwire in-ear mix as opposed to a wireless one?
Definition
Stationary performers.
Term
What is the first thing you need to do to obtain custom ear molds?
Definition
Go to a hearing aid center or an audiologist and have impressions taken of your ears.
Term
How can an ambient microphone fed into a musician’s in ear monitor mix help the musician?
Definition
•It helps the musicians hear the crowd response.
•It helps with localization when using isolating molds.
•Allows communication on stage.
Term
Explain why a monitor wedge would be used in combination with an in-ear mix.
Definition
Low end supplement.
Term
What is multi-band limiting?
Definition
It allows separate limiter control over multiple frequency bands.
Term
Name some techniques other than a wedge that are used to enhance the low end of an in-ear mix.
Definition
•Bass "shaker”
•Side fill subs.
Term
What is multimode fiber?
Definition
Has a short distance and lower bandwidth.
Term
What is single mode fiber?
Definition
Has long distance and unlimited bandwidth.
Term
What is tight buffer cable?
Definition
It is light weight, easy to terminate, for indoor use.
Term
What is loose buffer cable?
Definition
It has a greater resistance to temperature changes, used outdoors, and harder to terminate.
Term
What advantage does the focal point of an array offer?
Definition
It helps us determine accurate splay angles. The point at which a listener in the “far field” perceives the sound originating.
Term
What are the two primary factors that affect array performance?
Definition
•Coverage angle of an individual speaker.
•Splay angle between adjacent speakers.
Term
What are four basic types of point source arrays?
Definition
•Point Source Wide (splayed)
•Point Source Narrow (Tight)
•Point Destination (Split Xfire)
•Exploded (Split Point Source)
Term
What type of array is recommended for front fill applications?
Definition
•Split Parallel
•Flown Center Cluster
•Onstage Fill
Term
At what point should front fill speakers overlap?
Definition
6dB down point (2k) at the first row of listeners.
Term
Where/Why are delay fills used?
Definition
•Outdoors: to overcome the natural attenuation of high frequencies by the air. •Indoors: To increase the direct to reverberant sound ratio
Term
What is a fictitious source?
Definition
A point used for the time reference of a system. All speaker systems are delayed to this point.
Term
Name some important considerations when using delay towers.
Definition
To maintain the same axis as the mains. Many small zones are more effective than 1 big one. Don’t crank them up, make them transparent to the mains (unless a new visual reference is established). Pursue stereo at your own risk.
Term
What is the difference in level between half space and quarter space?
Definition
10log4 - 10log2 = 6 - 3 = 3dB
Term
What is so important about a horn’s cut off frequency?
Definition
The lowest frequency a horn can safely produce and maintain acoustic loading.
Term
Explain the standard power up and power down sequence for a pro audio system.
Definition
•Amps on last
•Amps off first
Term
Name three methods to test a loudspeaker driver.
Definition
•Battery (Cone Drivers Only)
•Sine Wave Sweep Station
•DMM
Term
Name the two modes used with a DMM when testing loudspeakers.
Definition
•Continuity
•Ohms
Term
Name three benefits of using Ferrofluid.
Definition
•Heat dissipation (power handling)
•Coil Centering
•Mechanical Damping (fidelity)
Term
Name three types of material used to make compression driver diaphragms.
Definition
•Beryllium
•Titanium
•Aluminum
Term
Name two benefits of adopting a thorough labeling scheme for your audio system.
Definition
•Helps with quick set-up
•Helps with identification of bad components
Term
Networks can be classified using 2 properties. Name them.
Definition
Physical and Logical
Term
Name the three common network topologies.
Definition
•The Ring
•The Star
•The Bus
Term
What is the difference between baseband and broadband transmission?
Definition
•One send binary values directly as pulses of voltage of current.
•The other is a multiple channel baseband.
Term
What is the difference between single ended and differential?
Definition
•One is Unbalanced: all data lines share one ground
•The other is Balanced
Term
What is asynchronous transmission?
Definition
A communications strategy that uses a start and stop bit to indicate the beginning and end of a transmission.
Term
What is synchronous transmission?
Definition
A communications strategy that uses timing to control transmissions.
Term
What is isochronous transmission?
Definition
Means time sensitive. Its operation is dependent on constant time intervals.
Term
What is cobranet technology?
Definition
A combination of hardware, network protocol, and firmware that allows us to send audio over Ethernet in real time.
Term
How many channels of digital audio can a system using cobranet carry on a 100Base T network?
Definition
64 channels
Term
What is the job of a “conductor” in a network using cobranet?
Definition
It is a time keeper.
Term
What does “10/100base T” tell you about a network?
Definition
•1/100 = Speed
•Base = Signal type.
•T = Cabling
Term
What is data terminal equipment?
Definition
Anything that produces or consumes data on a network.
Term
Give two examples of data communication equipment.
Definition
•Hub
•Switch Router
•Network interface card
Term
What is a protocol?
Definition
Specifies a common set of rules and signals the device on the network uses to communicate.
Term
What three things does OSI allow us to do concerning protocols?
Definition
•Provides a common way to analyze protocols
•Allows one to compare protocols
•Helps troubleshoot network problems.
Term
What is a MAC address?
Definition
It is 6 bytes long, often noted in hexadecimal. Cannot be changed it is burned into hardware. No two are the same. It is used to identify a node on a network.
Term
What layer of OSI does an IP address operate?
Definition
Layer 3
Term
What are the two ways an IP address can be assigned to a node on a network?
Definition
Static and Dynamic
Term
Which OSI layer handles port access?
Definition
Layer 4 (Transport Layer).
Term
What is a Baseband transmission?
Definition
It sends binary values directly as pulses of voltage or current.
Term
What is a broadband transmission?
Definition
This is a multiple channel baseband transmission.
Term
What does "single ended" mean?
Definition
Unbalanced: all data lines share one ground.
Term
What does "differential" mean?
Definition
This means that data lines are balanced.
Term
What does “10/100” tell you about a network?
Definition
It is the speed.
Term
What does “T” tell you about a network?
Definition
The type of cabling.
Term
What does the "base" tell you about a network?
Definition
It is the signal type.
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