Audio Principles of Design

Question 1

When creating a schematic diagram of audio signal flow, you should include:

Answer 1

Microphones
Mixers
Switchers
Routers
Processors

Question 2

SPL should always fall between

Answer 2

0 and 140 dB SPL

Question 3

What’s this formula used for?

Answer 3

Decibel change for power

Question 4

You’ll need this formula to calculate _______________

Answer 4

Decibel changes in sound pressure level (SPL) over a distance

Question 5

“Zero Reference” is also known as __________

Answer 5

“Reference Level”

Question 6

0 dBu is equivalent to _____

Answer 6

0.775 Volts

Question 7

0 dBv is equivalent to _____

Answer 7

1 Volt

Question 8

Consumer audio level is often expressed as ____ dBv

Answer 8

-10 dBv

Question 9

Line level should be between __ and __ dBu

Answer 9

0 and +4 dBu

Question 10

Which SPL meter setting is mostly used to closely responds human hearing.

Answer 10

A-weighting

Question 11

Which SPL Meter Class is designed to only support A-weighting, and intended for general use

• Class 0
• Class 1
• Class 2
• Class 3

Answer 11

Class 2

Question 12

For speaker coverage, it takes into account which of the following?

A. Ceiling Height
B. Listeners ear-height
C. Speaker’s angle of coverage
D. Number of listeners

Answer 12

A. Ceiling Height
B. Listeners ear-height
C. Speaker’s angle of coverage

Question 13

The formula to calculate the _______________ is as follows:

Answer 13

coverage area of a loudspeaker

Question 14

What are the three loudspeaker coverage layouts?

Answer 14

Edge-to-Edge

Partial Overlap

Edge-to-Center

Question 15

This formula is to calculate speakers wired in parallel with __________ impedances

A. Same

B. Different

C. Varying

D. Regulated

Answer 15

B. Different

Question 16

To calculate the total impedance in a parallel circuit , with each speaker with the __________ impedance

Answer 16

Same impedance

Question 17

For program audio, what’s the recommended amplifier’s headroom?

Answer 17

20 dB

Question 18

Typical sound pressure level at listeners position for speech applications is ____ dB SPL

Answer 18

70 dB SPL

Question 19

Formula to calculate ____________

Answer 19

Electrical Power Requirements

Question 20

Loudspeaker ability to convert one form of energy into another

Answer 20

Sensitivity specification

Question 21

Amplifier’s voltage remains the same regardless the number of loudspeakers connected to it

• True
• False

Answer 21

True

Question 22

Microphone that picks up sound uniformly from all directions

Answer 22

Omnidirectional

Question 23

Mics usually worn by users

A. Lavalier
B. Handheld
C. Ceiling
D. Gooseneck

Answer 23

A. Lavalier

Question 24

PAG/NAG stands for ____________

Answer 24

“Potential Acoustic Gain” and “Needed Acoustic Gain”

Question 25

To work properly, a sound system must accomplish three things:

Answer 25

1. Loud enough 2. Intelligible 3. Remain Stable

Question 26

For a typical speech reinforcement system, that level is around _______ to ______ dB SPL

Answer 26

60 to 65 dB SPL

Question 27

Speech signal-to-noise ratio is ____dB

Answer 27

25 dB

Question 28

If a sound reflection arrives at the listener 50 to 80 milliseconds later is considered: A. An asset B. Echo C. Reflection D. Refraction

Answer 28

B. Echo

Question 29

At which SPL levels listeners could complain about being too loud?

Answer 29

85 to 90 dB SPL

Question 30

Gain before feedback is referred to as

Answer 30

"Potential Acoustic Gain (PAG)"

Question 31

What is: Equivalent Acoustic Distance (EAD) ?

Answer 31

Farthest distance from the source without need for amplification

Question 32

What's the purpose of NAG calculation?

Answer 32

to determine how much Acoustic Gain is Needed to deliver the same level to listeners

Question 33

PAG calculation deals with equipment True or False ?

Answer 33

True

Question 34

PAG deals with actual equipment and comprises _______ distance factors in its calculations

Answer 34

Four

Question 35

NOM stands for

Answer 35

Number of Open Mics

Question 36

the threshold of human hearing is 0dB SPL at _____ kHz ?

Answer 36

1 kHz

Question 37

PAG and NAG calculations to ensure audio system is A. Loud enough B. Intelligible C. Stable D. Optimal

Answer 37

C. Stable