The document discusses the key components of a public address (PA) system, including microphones, speakers, a sound mixer, amplifier, and cables. It describes the functions of a sound mixer in combining different audio signals and inputs. The document also covers different types of audio cables and connectors used in PA systems like XLR, RCA, TS, TRS, and TRRS, and discusses the differences between mono and balanced vs unbalanced audio connections.

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PUBLIC ADDRESING SYSTEM (PA SYSTEM)
IMPORTANT COMPONENTS OF A PA SYSTEM
 MICROPHONE/MIC (WIRED & WIRELESS)
 SPEAKER/LOUD SPEAKER
 SOUND MIXER / MIXING CONSOLE
 SOUND AMPLIFIER/POWER AMPLIFIER
 MUSIC PLAYER
 CABLES
SOUND MIXER / MIXING CONSOLE
 A sound mixer /mixing console is an electronic device for
combining sounds of many different audio signals.
 Inputs to the console include microphones being used by
singers and for picking up acoustic instruments, signals from
electric or electronic instruments, or recorded music.

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 A mixing console is also known as an audio mixer, audio
console, mixing desk, sound mixer, soundboard.
CABLES & PORTS
Auxiliary Port (AUX)
An auxiliary port (AUX) literally just means an additional
audio input method.
An auxiliary port (AUX) is a type of standard
communications port on a device that accommodates audio
signals for:

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1. MP3 players.
2. Headphones and headsets.
3. Microphones
4. Speakers
5. And other audio devices
MONO & STEREO
Two types of signal can be transmitted from the audio source
 A mono signal uses only 1 audio
 Stereo signal uses two audio channels (left and right).
 stereo signal simulates “natural” hearing by creating the
impression of sound coming from different directions.
 This is accomplished by the separate audio channels
producing sound in two different speakers (or stereo
headphones).

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Balanced VS Unbalanced Audio
Balanced audio is all about interconnecting audio equipment
and transmitting signals in a “balanced” manner.
 A balanced output has two signal phases (or a hot and
cold signal) per channel. Each phase has an equal
impedance relative to ground, hence the name balanced.
 A balanced mono cable typically has at least three
conductors (TRS) to carry the signal to the headphones.
A balanced stereo cable has at least five conductors
(TRRRS).
Advantage of Balanced Audio
The advantage of balanced connections over unbalanced
connections is the canceling of noise interference via a
technique named Common Mode Rejection (CMR).
interference that adds equally to both phases creates no
difference between them and is canceled out when they are
recombined by the amplifier. This canceling process of noise
while preserving the original sound is known as CMR.
With the above two concepts, you should know that you can
send 4 types of signal from the output (amplifier for example)
via a cable to a pair of headphones.

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1. Unbalanced mono
2. Balanced mono
3. Unbalanced stereo
4. Balanced stereo
XLR CABLES
 The XLR connector is a type of electrical connector primarily
found on professional audio, video, and stage lighting
equipment.

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You will find that XLR connectors (3 pin pairs, 4 pin, and 5
pin) are also a common choice for stereo balanced
headphones.
XLR5 Female (L) XLR5 Male (R)
XLR connectors have been the standard balanced connector
in the professional audio market for decades.
 4-pin XLR connectors have been used for the connection
between balanced headphone cables and a headphone
amplifier.

RCA CABLES
 An RCA connector, sometimes called a phono connector or
(in other languages) Cinch connector, is a type of electrical
connector commonly used to carry audio and video signals.
 The name RCA derives from the Radio Corporation of
America,

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

Headphone Jack and Plugs/ Male Connector (L) Female
Connector (R)
Different sizes of headphone jacks/plugs
 6.35mm Connector / ¼ inch connector
 4.4mm Connector
 3.5mm Connector / mini / ⅛ inch
 2.5mm Connector / Sub-mini


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TS CABLES
 TS cables are generally used for mono, unbalanced signals.
 TS connectors have two contact points separated by an
insulator ring: tip (T) and sleeve (S).
 The audio signal travels over the tip while the ground uses the
sleeve.
 That means T is positive and S is ground.


TRS (Tip-Ring-Sleeve) connectors
TRS cables can be used for mono, balanced signals as well as stereo
signals.

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4 conductor plug (TRRS)
5 conductor plug (TRRRS)

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TRRRS connectors are used to support
balanced stereo signal.
If the headphone cable comes with a standard 3-pole TRS stereo
connector, it must be unbalanced, regardless if it is a larger 6.35 (¼”)
or smaller 3.5mm (⅛”) connector. A 3-pole connection means the
grounds are tied together and will not work with a balanced output.

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Watch these videos for more info
1. https://www.youtube.com/watch?v=r2JVFgSgcCc
2. https://www.youtube.com/watch?v=HKpV30pjvIo
3. https://www.youtube.com/watch?v=4uGYPgSTrm0
4. https://www.youtube.com/watch?v=Shtwr8-P0zs
5. https://www.youtube.com/watch?v=QGYswg0OcJo