General questions Flashcards
Successfulley communication design intent requires a \_\_\_\_\_\_\_\_\_\_\_\_\_ approach Structured Random Linear Phased
Phased
The Program Phase consists of: Needs Analysis Verification Documents Design Specifications Program Report Construction drawings
Needs Analysis
Program Report
The Design Phase consists of: Needs Analysis Verification Documents Design Specifications Program Report Construction drawings
Design Specifications
Construction drawings
Verification Documents
The Program Phase is also called the: Discovery phase Concept Design Phase Construction Phase Schematic Phase Briefing Phase
Concept Design Phase
Briefing Phase
Confirm scale using: A ruler The scale on the drawing Common Building elements A photocopy
Common Building elements
3" measured on a 1/8" scale is actually: 24' 32' 16' 8'
24’
Which drawing shows the space as if it were cut apart? Reflected ceiling plan Elevation Drawing Section Drawing Detail Drawing Block drawing
Section Drawing
Who are end users?
People paying for the project
People who operate the system day to day
Architect, designer, allied trades,
People who operate the system day to day
The eye can comfortably see how many degrees side to side? 8 10 15 30
15
Details and words can be seen how many degrees from centre? 5-15 10-20 15-30 5-30
10-20
Symbols and shapes can be seen how many degrees from centre 10-20 15-30 5-30 5-15
5-30
The limit of colour discrimination is how many degrees from centre 10-20 5-30 30-75 30-60
30-60
Is the vertical field of view oriented more above or below straight ahead?
below. 10 degrees when standing and 15 degrees when sitting
Optimal eye rotation is how many degrees below the line of sight 15 25 30 40
30
Optimal eye rotation is how many degrees above the line of sight 15 25 30 40
25
Comfortable head rotation is how many degrees side to side? 30 45 55 60
45
Two ways to determine the minimum distance to the screen are:
15 degrees from the top of the image to the eye; screen width
45 degrees right to left and 1/2 the screen height
15 degrees from the top of the image to the eye; screen width
What is the standard seated eye height 30" 48" 50" 80"
48” or 4’
How much circulation space does a person need? .5m .8m 1m 2m
1m
Passageway clearance should be.. 24" 36" 48" 56"
36”
From the edge to a table to the nearest obstruction should be at least: 24" 30" 36" 48"
48”
Minimum text height should be furthest viewer divided by: 99 120 150 300
150
Furthest viewer should be screen height x \_\_, \_\_, \_\_ for Observing content, Inspecting content with clues, inspecting content without clues? 4, 5, 6 1, 2, 3 10, 5, 3 8, 6, 4
8, 6, 4
Furthest viewer uses what measurement: Image diagonal Image height Image width viewing task
Image height
Closest viewer uses what measurement: Image diagonal Image height Image width viewing task
Image width
A good viewing cone or area is how many degrees off axis in either direction? 30 45 60 85
45
You have a 16:9 screen and know the diagonal, how do you determine the width?
Use a^2+b^2=c^2 to determine the 3rd number in the ratio (18.36). 16/18.36 = x/diagonal. Same applies for any of the dimensions.
What measures the light coming from a source such as a light bulb? Refractance meter Incidence meter Spot meter Lumenance meter
Incidence meter
What measures the light reflecting off a surface? Refractance meter Incidence meter Spot meter Illumenance meter
Spot meter
An incidence meter uses which units of measurement? Pick 3 Lux Candelas Lumens Foot Lamberts Footcandles Candle power
Lumens, Footcandles, Lux
Lumens is the most common
An spotmeter uses which unit of measurement? Lux Candelas Lumens Foot Lamberts Footcandles Candle power
Candelas. Technically candelas per square meter
A measured contrast ratio is what?
Average luminance of the 8 white squares divided by the average luminance of the 8 black squares
Minimum contrast ratios for passive viewing, basic decision making, analytical decision making, and motion video is (__, __, __, __)
6: 1, 16:1, 32:1, 100:1
7: 1, 15:1, 50:1, 80:1
10: 1, 20:1, 40:1, 80:1
3: 1, 13:1, 40:1, 60:1
7:1, 15:1, 50:1, 80:1
Projector throw ratio = Distance/screen width Distance/screen height Screen width/distance Screen height/distance
Distance/screen width
When determining a projector's brightness, what de-rating value do you use? .10 .50 .75 .90
.75
How do you measure the brightness of an existing projector?
Using an all white image and a spot meter, measure and average the lux in all 9 zones, then multiply by the hight and width in meters
What should the difference be between white image brightness and the work surface
+/- 3x
What dB change is the smallest perceptible change noticable? 1 3 6 10
1 dB
What dB change is a just noticable change? 1 3 6 10
3dB
What dB change is twice or half as loud? 1 3 6 10
10dB
Doubling or halving the distance produces what dB change? 1 3 6 10
6dB
Which x-log formula is for Power?
10 log
20 log
10 log.
Which x-log formula is for Distance?
10 log
20 log
20 log
Which x-log formula is for Watts?
10 log
20 log
20 log
Which x-log formula is for Voltage?
10 log
20 log
20 log
What is the reference or zero dB level for sound pressure? dB SPL
Basically zero
What is the reference or zero dB level for Voltage dBV?
1 volt
What is the reference or zero dB level for Voltage dBu? small u
.775 volts
What is the reference or zero dB level for Voltage dBW?
1 watt
What is the reference or zero dB level for Voltage dBw? small w
.001 watt or 1 mW
Sound pressure SPL should be between what values? 3-90 1-120 0-140 3-10
0-140 dB
Microphone level dBu should be between what values? 0-140 -60 - -50 0-10 -10 - -45
-60 - -50 dBu which is well below .775 volts
Line level dBu should be between what values? 0-4 1-140 -10 - -30 0 - -60
0-4
Consumer audio level is \_\_ dBV 0 4 -20 -10
-10dBV or .316 volts
How many dB above ambient should a space generally be? Signal to noise ratio \+10 \+25 0 -10
+25 dB A-weighted
If background noise is measured at 35 dB, the system should put out 60 dB
If you are designing an audio system in a multi-purpose room, should you design it for a standing or seated audience?
Standing
Headroom dB for a speech application is: 6dB 10dB 20dB 25dB
10dB
Headroom dB for a program audio application is: 6dB 10dB 20dB 25dB
20dB
For multiple microphone placement what is the 3:1 rule?
Mic to mic separation is 3x the mic to mouth distance
As a general rule what is the target SPL for speech reinforcement? 25dB 50dB 65dB 75dB
65dB
Reflected audio arriving 50-80 milliseconds after direct audio is considered good or bad?
Bad. It’s an unwanted echo. Earlier than 50-80ms is reinforcement.
To determine if amplified audio is stable you have to calculate what?
Gain before feedback
What is Equivalent Acoustic Distance or EAD
The furthest distance one can go away from the speaker without needing amplification. Usually about 4 feet
Generally what is the Feedback Stability Margin FSM? 0dB 3dB 6dB 10dB
6dB
PAG must be about 6dB greater than NAG
Standards serve as what? General guidelines Rule of law Common platform for understanding Best practices
Common platform for understanding
In the heirarchy of design consultation what is the highest level? Project Documentation Regulatory Requirements Manufacturer's Documentation National Standards
Regulatory Requirements
Which 2 characteristics of light are most important to designers. Source Brightness Colour temperature Structure
Brightness
Colour temp
The units of measurement for brightness are: (3) candelas per square meter kelvin nit footlambert foot candle lux
nit
footlambert
lux
Light falling on a surface is___?
Luminance
Illuminance
Illuminance
Light relected from a surface is___?
Luminance
Illuminance
Luminance
The units of measurement for reflected light are: (2) candelas per square meter kelvin nit footlambert foot candle lux
Lux
Foot candles
Direct light is measured with a what?
Incident Light meter
Spot meter
Incident Light meter
Indirect light is measured with a what?
Incident Light meter
Spot meter
Spot meter
A "warm" CCT is below what Kelvin? 2500K 3200K 4000K 6000K
3200K
A "cool" CCT is above what Kelvin? 2500K 3200K 4000K 6000K
4000K
CRI Colour Rendering Index measures what?
How accurately a light source can replicate a desired set of parameters
Task lighting should be between what values? 10-50 lux 100-500 lux 300-700 lux 200 to 500 lux
200-500 lux
Ambient light hitting a front projection screen should be less than.... 10 lux 20 lux 50 lux 100 lux
50 lux
How much of a dimmer's capacity should be used for incandescent light? 50% 75% 80% 100%
80%
How much of a dimmer's capacity should be used for flourescent light? 50% 75% 80% 100%
50%
As a general rule, the colout temperature setting on a camera should be set to what? 3000K the colour temperature of the lighting Daylight temperatures Maximum
the colour temperature of the lighting
What is the minimum grade fastener that you should specify?
SAE-2, ISO 4.6
SAE-5, ISO 8.8
SAE-8, ISO 9.8
SAE-5, ISO 8.8
What does a block diagram illustrate?
Signal path through a system. Read left to right and top to bottom
What are the two methods of cooling a rack? Normalization Pressuration Substration Radiant Evacuation
Pressuration and Evacuation
What is the maximum load for a breaker or circuit? 50% 75% 80% 90% 100%
80%
What is the purpose of an isolated groud circuit?
Minimize buzz or hum caused by a problematic ground loop. Grounding is isolated from the receptacle mounting.
What is the most popular conduit in AV Flex conduit Intermediate conduit Electrical Metal Conduit Rigid Metal conduit
Electrical Metal Conduit
What are the allowable conduit fill percentages? 1, 2, 3+ cables. 30/60/90% 50/75/20% 53/31/40% 60/30/75%
53/31/40%
When do Jam Ratios come into effect?
When installing 3 cables. Keep it away from 3
When should a junction box be specified? After 100m Every 90 degree bend When exiting a room Every 180 degrees
Every 180 degrees
Which has a greater effect on the speed of sound
Altitude
Air temperature
Air temperature
What is the speed of sound?
1000 ft/sec, 310 m/s
1130 ft/sec, 344 m/s
2000 ft/sec, 400 m/s
1130 ft/sec, 344 m/s
Wavelength is..?
speed/frequency
Can a diffuser work over all frequency ranges?
No. A diffuser of a specific size only works in a specific frequency range
What is a flutter echo?
A series of reflections that continue to bounce back and forth between parallel hard surfaces.
Is having room dimensions that are multiples of each other ok?
No. A cube is the worst
The reverb time of a space (RT60) is what?
The time it takes for a wave to repeat itself
The time it takes sound to increase by 60dB
The time it takes for sound to decay 60dB.
Noise Reduction Coefficients of what are considered reflective? Below 0.2 Above 0.2 Equal to 10dB zero
Below 0.2
Above 0.4 are absortive
A Speech Privacy Rating of what is adequate. 0-20 20-40 40-55 55-65
40-55
Does the Speech Privacy Rating apply to all sounds?
No, only the speech frequencies
If you want to quantify impact sound absorption of a material, which measurement do you use? STC IIC FTP NRC
IIC - Impact Insulation Class. 28-85, less absortive to more absortive
What is the sampling rate for an audio CD? 8kHz 44kHz 96kHz 1.2 MHz
44kHz
What’s the trick for figuring out the bandwidth of 4:2:, 4:1:1, or 4:2:0?
For 4:4:4: it’s Horiz x Vert x bit x FPS x 3
Anything else it’s four fourths HxVxBxF + two fourths HVBF + two fourths HVBF etc
Which are the lossless codecs? JPEG2000 H.264 MPEG-1 MPEG-2 VC-1
JPEG2000
H.264
Which are the lossey codecs? JPEG2000 H.264 MPEG-1 MPEG-2 VC-1
MPEG-1
MPEG-2
VC-1
What’s the difference between intraframe and interframe compression?
Intra compresses each frame individually, file sizes are larger. Lossless
Inter only send the difference between frames, files are smaller. Lossey
HDMI 1.4's bandwidth is: 5.4 Gbps 10.2 Gbps 16.4 Gbps 18 Gbps
10.2 Gbps
HDMI 2.0's bandwidth is: 5.4 Gbps 10.2 Gbps 16.4 Gbps 18 Gbps
18 Gbps
How are HDMI and DVI similar?
HDMI is the same but with the addition of audio
Which signal id TDMI and which is LVDS?
HDMI and DVI use TDMI
Display Port uses LVDS
What does EDID do
EDID is how a sink describes its capabilities to a source to ensure they work together.
What would you use to organize your EDID information?
Let the manufacturer do it
Let the control system manage it for you
Create a truth table
Create a truth table
When setting the gain structure, which one is set last? Microphones Audio mixer DSP Preamps Amplifier
Amplifier
Generally speaking what is the gain level range on microphones?
35dB to over 60dB.
Handhelds, 35 and the further you go out to the ceiling mic, over 60dB
Which network uses physical addresses to communicate? LAN WAN PAN Internet
LAN uses the MAC address of the device
Can you place a device on more than one VLAN?
Yes
What is the purpose of a VLAN? Increase network speed Increase network stability Segragate a network Increase security
Segregate a network
What is the purpose of Reserve DHCP?
It’s a method of reserve static IP adresses on a DHCP network
What does Domain Name Service DNS do?
Translates a name into an IP address.
Which transport protocol ensures data delivery?
TCP - Two way communication to ensure that all data arrived complete. Slower but guaranteed.
UDP just fires it across and doesn’t care if the data was received. Faster, used when real-time communication is required.
What is the minimum bandwidth required by Dante?
10Mbps
100 Mbps
1000 Mbps
100 Mbps
When streaming on a network, what poercentage of the bandwidth should you expect to be alloted? 10% 21% 33% 50% 100%
21%
In a network, consider that only 70% of the total bandwidth is available, and that streaming can only use 30% of that.
For these 3 uses, how much latency is acceptable?
Videoconferencing, Hi-fidelity audio, Streaming desktop video
50 milliseconds, 10 milliseconds, 3 seconds
200 milliseconds, 50 microseconds, 1 second
300 milliseconds, zero, 1 minute
10 milliseconds, 10 microseconds, 1 second
200 milliseconds, 50 microseconds, 1 second
Multicast transmissions are always delivered by:
TCP
UDP
UDP, no exceptions
In network security what is the CIA triangle? Control, Instantanious, Acceptance Conception, Intermediate, Analysis Confidentiality, Integrity, Availability Constant, Internal, Area
Confidentiality, Integrity, Availability
At what stage of the project is it best to determine the customer's security needs? Needs Analysis Project Award Installation Sign off
Needs Analysis
What is the triple-A of access control?
Always Allow Access
Abide, Abate, Arrange
Authentication, Authorization, Accounting
Authentication, Authorization, Accounting
When doing a risk analysis, what is the most common response? Avoid Accept Transfer Mitigate
Mitigate
If you encounter conflicting regulations or codes, which one should be followed?
The most restrictive.
In projection what contrast ration is needed for basic decision making?
7: 1
15: 1
50: 1
80: 1
15:1
7: 1 - passive viewing
15: 1 - basic decision making
50: 1 - analytical decision making
80: 1 - full motion video
How many viewing areas a used to determine the average contrast ratio on a screen? 1 3 5 9
5
What is the best method to determine if audio and video are synced? Check the manufacturer's specs Just eyeball it Blip and Flash Spoken word like a newscast
Blip and Flash
