Sound reinforcement I

T

(T F) A chorus effect needs to do two crucial things, delay a copy of the signal and add a flanging effect into that copy.

False

(T F) A disadvantage to digital mixers is that they share multiple I/O (Analog to digital converter) boxes.

True

(T F) A high dampening factor means my amplifier will have more control over stopping and reversing the movement of my speaker's driver.

True

(T F) A linear phase filter preserves the time relationship of a complex waveform and, therefore, eliminates the distortion of transients in dynamic music.

True

(T F) An active speaker system will have an amplifier, crossover, and protection built into it.

False

(T F) Direct radiator drivers are highly efficient at transmitting sound, they can be up to 80% efficient.

True

(T F) In a digital mixer no audio physically runs through any control device on the control surface.

True

(T F) It is common to have multiple engineers during highly complex shows to work as a team and manage the mix.

True

(T F) It is generally agreed that most humans cannot hear Total Harmonic Distortion below 0.5%

False

(T F) It is important to maintain a static, or unchanging mix, except for the lead vocal and solos.

True

(T F) Power compression is caused by two things: 1) The heating up of a driver's voice coil which causes the impedance of the speaker to increase. 2) As speakers are pushed harder they near their mechanical limits and they become non-linear.

True

(T F) The Amplifier's output wattage should be twice as high as the power handling capability of the loudspeaker.

True

(T F) The Class A Amplifier is biased so that the transistors are always conducting electricity, even if there is no input signal present.

True

(T F) The decibel is named after Alexander Graham Bell.

F

(T F) When a compressor has a high ratio and long release time you may hear the level of the audio rise and fall. This effect is called breathing.

True

(T F) When designing a sound system for outdoor operation we must note that it will likely sound quieter than if it were in an indoor venue and we have to consider surrounding buildings for any echoes they may cause.

the amplifier creates a crossover distortion.

A class B amplifier will more than likely never be used in live sound because...

infinity:1

A compressor set to have "brick wall" limiting will have a ratio of...

control the dispersion of the sound, increase the driver's efficiency, reduce the midrange spread of the driver

Horns are used in conjunction with direct radiator drivers to...

control data

Data that is generated as a result of the user setting a parameter.

Audio stream data

Data that is generated die to sending the audio through sending the signal from the ADC to a routing module.

Class D

This amplifier type uses pulse wave modulation (PWM) to amplify signals.

Adjustable Q, Adjustable frequency, adjustable gain

Select all of the following attributes of a parametric equalizer. Adjustable Q Fixed Q Adjustable Frequency Fixed Frequency Adjustable Gain Fixed Gain

both channels of the amplifier operate independently.

When I am operating my amplifier in stereo mode...

cone breakup

When a direct radiator driver's cone moves at different rates because it is not rigid entirely rigid, it will cause...

layering

allows for the sharing of physical controls across multiple functions on the console.

your low frequency audio content

Dampening factor is only an issue for..

all pass filter

A ___ is an EQ that leaves all frequencies in tact but allows us to manipulate the phase of our audio signal.

Direct Radiator Driver

A ____ radiates it sound directly into the air with out the assistance of a horn, chamber, or duct.

GFCI circuit

A ______ protects users from electrocuting themselves by constantly monitoring the current flow through itself.

the vertical and horizontal dispersion of a speaker

A speaker's polar plot will typically show...

Acoustic suspension

Air is trapped inside of the enclosure that allows for a buildup of pressure behind the driver. This trapped air acts like a spring to return the driver's cone to it's original resting state.

is the physical XLR, 1/4 inch, fiber optic, or other connection into the console, must be bound or patched to another input.

An input port...

latency

Digital processing is a serial process of several discrete steps where each step takes a small amount of time to complete. This amount of time is known as _____.

2400 Watts

How many watts can you draw from a 20 amp circuit breaker in the U.S?

5

My powered speaker runs on 600 watts and I have 120v power supplied by my electrical company. How many amps will the speaker draw when running at its maximum?

Both choices 1 and 2 are acceptable ways to keep vocals in the mix.

One way to get make it easy to hear vocals in a mix is to...

Voltage squared / resistance

Power =

EQ, busing, internal effects, matrix sends

Select all that apply: Most digital consoles offer which of the following options? EQ Busing DCA's Internal effects matrix sends

impulse response

The ____ of a room gives us information about the intensity of reflections, or reverberation, inside the space.

snapshot

The process of copying and saving the mixer's state ant any time.

scene

The state and settings of a mixer at any instant.

Critical Distance

The transitional boundary between the direct and reverberant audio field in a room is called the...

Ported enclosure

This enclosure has an opening to the outside that functions as a Helmholtz resonator.

Dipole speaker system

This is a baffle that allows sound waves to exit from both sides of the driver to reproduce the final sound.

15 AMP, 20 AMP

What are the two most common amperage ratings for U.S. circuit breakers?

The output signal will clip.

What happens if you exceed the maximum output voltage of a power amplifier?

In a parallel wiring setup

When "Daisy Chaining" speakers together you are actually hooking up the speakers...

ITU-R-468

When considering an Amplifier's signal to noise ratio, an engineer must take note of the weighting system used to measure the noise. If a ______ is used, the midrange frequency content will be emphasized more than any other weighting system.

Plan for high power amplifiers, plan to use multi channel snake

When designing a system for music, you need to...

increase the direct to reverberant sound ratio, remove much of the low frequency noise in you sound system

When designing a system for speech, you need to...

both channels of the amplifier operate together to double the output voltage

When operating an amplifier in bridge mode...

1/3 of an octave only when placed at maximum boost

When using an 31 band graphic EQ, the frequency band filters adjust ____.

Bass, Drums, Lead vocal

Which of the following are considered the foundations of the mix? (Mark all that apply)

CAT5e/CAT6

Which of the following is not a Digital audio format?

Make any adjustments to the input list as modifications arise

Which of the following is not a performance task an engineer should focus in during the show?

muting prevents spill and possible feedback

Why should an engineer mute channels when they are unused?

Constant-Q

___ is a graphic EQ where the bandwidth of each filter does not change when the slider is moved.

Spectral Mixing

____ is the art of removing or boosting frequencies of each instrument to give it it's own space and separation.

sensitivity

____ is the specification that will tell about the efficiency of a speaker.

DIR

_____ allows us to take any analog input and route it to any digital input port.