Reinforcement 1 Final Flashcards
Sound system, (PA system) PA stands for what?
Public Address system.
What are the two sources of signal in a sound system?
- Microphones
2. Direct Boxes
What are the two ways of transmitting signal in a sound system?
- Snake, a condensed collection of XLR cable sends and receivers.
- Wireless transmitters.
What is used to mix the signals in a sound system?
Mixer.
What are some kinds of signal processors?
Equalizer: adjusts tonality of the signal.
Feedback Eliminators: special equalizers that can detect feedback and automatically adjust the tone to reduce or prevent squeals.
Reverb: adds ambient wash of echo that simulates a large room
Effects: other effects can be added such as delay
What are some elements of the amplification portion of the sound system?
Crossover: in larger systems it helps to split the signal into different frequency ranges so the system can better handle the full signal.
Amplifiers: amplifiers power up the small signal sent from the mixer so that it is loud enough for the congregation to hear.
Speakers: The speakers are where the electronic signal is converted back to sound and directed out into the building.
Monitors: Monitors are also speaker but are used so the music team and pastor are able to hear themselves.
Components of a basic sound system:
Microphone
Mixer
Amplifier
Speakers
Types of cable/connectors:
XLR RCA 1/4" 1/8" Banana Speakon
Balanced Cables
3 conductors, 2 hot leads and a ground Tip, Ring, Sleeve - TRS Almost all microphones are balanced Balanced cables can be run long distances cancel interference Low Impedance
Unbalanced cables
2 conductors Tip, Sleeve - TS Almost all guitars are unbalanced 1 hot lead and a ground Unbalanced cables can only be run a max of 25ft. otherwise you risk picking up interference High Impedance - convert ASAP
Define Sound
Energy that travels through the air.
Sound energy is created by a vibrating source called a transducer.
Speed of sound?
1,120
What is a cycle?
one crest and one trough
Define frequency?
The number of times a wave completes its cycle in one second.
Explain pitch.
Each pitch had a fundamental frequency, or number of cycles per second.
What is a fundamental frequency?
The frequency that defines a pitch.
What are harmonics/overtones/partial tones?
The aspects of a sound wave the determine the character of an individual sound.
What is a wavelength?
The distance between the crest and the trough.
Lower frequencies have longer wavelengths and higher frequencies have shorter wavelengths.
What is amplitude?
The amount of energy in a specified sound wave.
This can be qualified with decibel sound pressure level.
What is loudness?
a sound characteristic that involves the listener, loudness is perceived and is not actually calculated.
What is the frequency of peak human sensitivity?
3000 Hz
What are the painful thresholds of sound amplitude (loudness)?
120dB - Threshold of discomfort
140dB - Threshold of pain
160 - Eardrum ruptured
What is the difference between dBspl and dBV?
dB SPL: sound pressure level
dBV: electrical voltage
the difference is the type of energy
dBV: certain sound equipment is made for certain sound levels
Mic Level: -55 to -30dBV
Consumer/Instrument Level: -10dBV
Professional Line Level: +4dBV
Professional (nominal) Line Level is ideal.
