Transcript Sound Design and Technology (Introduction)

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There are three basic types of sound systems
used in theatre:
Sound reinforcement
 Sound recording
 Sound playback
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Much of the same equipment is used in all three
configurations, just arranged in slightly different
order.
Microphone – a transducer that converts sound
waves into electrical energy.
Transducer – a device that converts one form of
energy into another
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A microphone is a type of transducer. It picks up sound
and converts it into a weak electrical signal.
Image:http://electronics.howstuffworks.com/gadgets/audio-music/question309.htm
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The signal from a microphone is sent to a
preamplifier in the mixer.
The preamp boots the power of the signal to the line
level for signal processing by the mixer.
Preamplifier – a device that increases the power of a
weak signal for use by subsequent stages in the
electronic circuit.
Mixer – a device used to combine two or more input
signals to create a blended output signal.
Multichannel mixers blend numerous input signals
and routes them to multiple output channels.
Line level – the standard operating voltage used by
mixers and signal processors.
Signal processing – the manipulation of transducer
input signals to change, blend, and enhance the
resultant output signal(s).
The flow chart of a basic, single-channel
sound reinforcement system.
Image:
http://www.prosoundweb.com/article/church_sound_developing_system_diag
rams_as_a_useful_road_map/
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After the sound has been processed, it is sent to
the power amplifier.
The power amp substantially increases the
power of the signal and sends it to the
loudspeaker.
Power amplifier – a device used to boost the
signal received from the mixer to a level that will
drive a loudspeaker.
In a recording system, sound is sent from a
microphone/input  mixer  computer (Digital
Audio Workstation, or DAW).
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In live recording, very little processing is used in order
to preserve the original sound.
In a playback system, sound is sent from a DAW
 mixer  Amplifier  Loudspeaker
A diagram that includes all three systems in
one: reinforcement, recording, and
playback.
Image: http://www.mediacollege.com/audio/01/sound-systems.html
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There are three basic types of microphones
used in theatrical sound design.
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Ribbon microphones use an extremely thin strip of
metal suspended between poles of a magnet to
transduce sound.
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Dynamic microphones consist of a magnet
surrounded by a wire coil.
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The air pressure of the sound waves moves the metal
ribbon back and forth, generating electrical energy.
They are extremely delicate and are typically only used
for recording or in the pit orchestra.
One end of the coil is attached to the mic’s diaphragm.
When sound waves strike the diaphragm, the
diaphragm and coil move and create electrical energy.
These mics are rugged and suitable for onstage use.
Images:
http://www.emusician.com/how-to/1334/ribbon-mics-explained/43628
http://www.diyaudiocomponents.com/rm6-full-kit
http://www.songsofthecosmos.com/encyclopedia_of_modern_music/D/dyna
mic_microphone.html
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Condenser Microphones are the most
electrically complex mics used in theatre sound.
The diaphragm is made of thin conductive material
and forms one plate of a capacitor.
 Capacitor – an electronic component composed of two
conductive places separated and insulated from each
other. Used to store an electrostatic charge.
 A constant voltage (v48 aka “phantom power”) is
applied across the capacitor plates.
 When a sound wave hits the diaphragm, the pressure
changes the space between the two plates. This alters
the voltage and creates electrical energy.
 Phantom power – a method of supplying DC power
through the microphone cable to operate condenser
microphones.
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Image:
http://vignette2.wikia.nocookie.net/microphone/images/4/41/Micdiagram02
569.jpg/revision/latest?cb=20140926144716