1. Name: _______________________ SPS0908
Class:________
SPS Reading Worksheet Packet
for the
Yamaha Sound Reinforcement Handbook
2. Section 1
A single complete cycle of an acoustical pressure wave consists of two components. What are
they?
compression and rarefaction
frequency
The rate of air pressure fluctuation is called the _________________ of a sound wave
The amount of time required for one complete cycle of a sound wave is called the
period
______________ of the wave.
1130
The speed of sound is ___________ feet per second
The physical distance covered by one complete cycle of a given frequency is called the
wavelength
___________________.
signal level
The amplitude of an audio signal is called the ________________________.
The time relationship of a sound wave or audio signal to a known reference is know as the
phase of a signal
___________________.
degrees
The phase of audio signals is measured in _________________.
What are the three basic purposes of a sound system?
to help people hear something, to make sound louder
for artistic reason,to enable people to hear sound in
remote locations.
Name two types of input transducers
air pressure or velocity microphones, contact pickup
Name 2 types of output transducers
woofer loudspeakers, full-range loudspeakers
3. Section 2
What does the term frequency response describe?
the relationship between the device's input &output with regard to signal frequency& amplitude
A Frequency Response Graph measures two components of an audio signal. What are they?
range of frequency and what fluctuations in output level occur within that range
octave
Pink noise generates tones at equal energy per ________________.
In a balanced circuit, what is the best means of reducing hum?
twisting the dual conductors
capacitance
Frequency Response problems in cabling are often due to ____________________ between signal
conductors.
Which component of a sound system is most susceptible to large variations in frequency
response?
loudspeakers
Frequency response problems with cables are most often caused by the cable’s
capacitance
______________________ between signal conductors.
frequencies
Every sound that we hear is a composite of sine waves a different ____________________ and
amplitudes
_____________________.
4. Section 3
What does “RMS” stand for?
Root Mean Square
How can you derive the RMS value of a sine wave mathematically?
the peak value can be multiplied by a constant
What device can be used to measure sound pressure levels?
sound level meter
(True/False) Human hearing has “flat frequency response.”
false
What two scientists first described the idea of “Equal Loudness Contours?”
Fletcher and Munson
What is another term used in the book to specify loudness?
phon
Between what two frequencies is the peak of human hearing sensitivity found?
3 and 4 kHz
Why are our ears most sensitive at the frequencies listed in the previous question?
it's where the outer ear's canal is resonant
What does a typical “loudness control” on a car stereo system do and why?
low SPL listing levels, this makes the music seem more natural at less earsplitting levels
5. Section 8
What is the difference between “Frequency Response” and “Frequency Range?”
frequency response reproduces the signals input, frequency range is just the original sound
graphically
Specifications can be represented in a typed (printed) form, or in a ________________ form.
White noise is….
unfiltered,unaltered thermal noise
Hz
White noise contains equal energy per _______________.
octave
Pink noise contains equal energy per_________________.
Why do we use Pink Noise instead of White Noise for system testing?
it is more useful as a loud speaker test and calibration signal
What does “EIN” stand for?
Equivalent Input Noise
What is audio distortion?
any unwanted change that occurs in an audio signal
amplitude phase
Audio distortion can alter the __________________, _________________ or create spurious
frequencies that were not present in the input signal.
Which form of distortion (THD or IMD) is more objectionable to our ears?
IND
Define Impedance….
the total opposition to flow of alternating current in an electric circuit and is measured in ohms
6. “Output Impedance” is also known as what?
source impedance
“Input Impedance” is also known as what?
the load impedance
What are some symptoms of impedance mismatching?
improper frequency response to excess distortion to incorrect operating levels to circuit failure
frequency
By its very nature, Impedance varies with _____________________.
Define the term “Crosstalk.”
signal leakage from one circuit to another,or between cables
What two types of coupling can cause crosstalk?
inductive, capacitive
7. Section 10
What type of microphone is the most common type in use today?
dynamics
condenser
The second most widely used type of microphone is the ____________________.
capacitor
Another word for condenser is ________________________.
Why is a condenser microphone able to respond quickly and accurately to sound pressure?
because the diaphragm of a condenser is not loaded down with the mass of coil
What is the primary difference between a condenser microphone and an electret condenser
microphone?
electrets have the amplifier and built-in battery , regular condensers just strictly us phantom power
What type of microphone is among the earliest types of mic ever developed?
Carbon
What is another term for a Pressure Response microphone?
PZM(Pressure Zone Microphone)
Name several scenarios where shotgun mics are used successfully.
broadcasting, film work, special effects, long distance pickup in sports events.
Name one scenario where parabolic microphones are used successfully.
nature recording
Define microphone pickup pattern (polar pattern).
the way in which the element responds to sounds coming in from different directions
transient
The smaller a microphone is, the better its _______________________ response will be.
8. Pages 182-185
The term “Mic Splitting” refers to…..
the division of the audio signal output from the mic to feed two or more different inputs
Overloading a microphone (connecting it to several console inputs simultaneously) can cause
what effects?
degraded frequency and transient response, and S/N ratio
What is the main purpose of a microphone splitter transformer?
to isolate the shield grounds between two protons of a sound system
What brand of transformers does the book refer to?
Jensen model JE-MB-C
9. Pages 149-182
What other terms are used to describe a mixing console?
mixer,mixing console,console,board,and desk
What does a preamplifier do?
boosts a weaker audio signal to a level suitable for further mixing and signal processing
What is the primary purpose of the preamp in a condenser microphone?
used to boost the weak -70dBu to -50dBu nominal output levels, or used as a impedance converter
pre post
The signal that is fed to the auxiliary busses can be set to ___________ or ____________ fader.
Why are effects auxiliaries fed post fader?
sends are still subject to the send level control,but they also track fader changes
When mixing monitors from FOH, why are auxiliary busses derived from a pre-fader setting?
channel fader changes that are made to fine tune the main house will not effect the band on stage
What does the term “Pan Pot” actually stand for?
panoramic potentiometer
If a console is said to be a 24 x 8 system, what does that imply about the console?
24input channels 8 primary mixing busses
How would one define the term “Headroom” in the context of audio consoles?
the difference between the max level a circuit can handle and the nominal level in the circuit
Name two types of console meters described in the book.
Peak Meters,and VU(volume unit) Meter
Balanced wiring is audio systems is used to eliminate what?
externally generated moise
10. Name some reasons why a high quality monitor mix is important….
the band can hear themselves clearly,the affect on the quality of sound in the house, feedback
What does the term “Ringing Out” refer to?
the method of tuning the equalization of each monitor channel.
Name one tool other than equalization that can be used to fight feedback.
graphic or parametric EQ