Download Basics of Audio Systems Audio Basic Signal Path Signal

NYC College of Technology
Dr. David B Smith
Professor John Huntington
©2004, all rights reserved
Audio
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The Electronic representation of Sound
Basics of Audio Systems
Basic Signal Path
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Signal Flow Charts
Outputs always connect to:
Inputs
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High level View
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Sound
Event
Transduction
Transducer
Audio
Equipment
Transducer
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Electrical
information
can now be
modified.
Modified
Electrical
information
converted
back to
Acoustical
energy.
Sound
Event
Acoustical
Energy
converted to
Electrical
Energy
Critical to design of systems
Drawn by designer
Used by crew to build system
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The conversion of one form of energy into
another
In our case, acoustical to electrical
Or, electrical to acoustical
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Signal
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Audio information
Can be either analog or digital
Analog is a voltage
Must travel along circuitry at close to speed of
light or be stored.
Otherwise, information is lost.
Signal Path
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The specific route that a signal travels
through the possible circuits
Voltage
Time
Gain
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Amplification factor of a circuit
Expressed in power or voltage
Every circuit has a gain between input and
output
Positive Gain
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If the Output power > input power
Negative Gain
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If the Output power < Input Power
Unity Gain
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If the power of the input = power of output
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Gain Stage
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Three levels of audio
Every circuit in the signal path that has a
control to modify the gain of that circuit.
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The Signal Paths in any System
Mic level
Line Level
Power Level
Basic System Relationships
Amplifier Speaker
Mic
INPUT
INPUT
Combining
and
Routing
INPUT
Types of Inputs
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Microphone
Playback
Synthesis
MIXER
OUTPUT
INPUT
OUTPUT
Playback
Recorder
Processor
OUTPUT
OUTPUT
Types of Outputs
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Outputs to speaker systems
Outputs to recorders
Outputs to broadcast
Outputs to Analysis or Monitoring
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Microphone
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Converts sound to electricity
Mixer
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Mixes multiple sources into one or more
outputs
Amplifier
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Boosts line level signal to power level to
drive speakers
Playback
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Plays back recorded audio data
Processing
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Changes the audio in some way
Speaker
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Converts electricity to sound
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