Transcript Mixers - Bramalea Secondary School Guitar

Mixers
An Introduction
Mixers: Overview
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A mixer is a device that is able to accept signals
from a wide variety of sources and then alter
them in some way by changing their level,
equalization and effects. The signals are then
routed to output connections. This is most often
to a pair of tracks (left and right), however most
mixers present several options.
Mixers take many forms from simple to
extremely complex.
Mixers: Applications
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Mixers are used in a wide variety of
situations.
These include: live concerts, public
address systems, recording studios, radio
stations, DJs, television studios and film
shoots.
A mixer is divided into four main
sections:
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Input Connections
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Channel Strip
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Master Section
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Output Connections
Input Connections
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This is the part of the mixer where the different
sound sources are plugged in. These may
include: microphones, direct boxes, guitars,
keyboards, CD players and turntables.
This is also the section of the mixer where
effects devices are patched in. Examples
include: compressors, reverb, chorus or delay.
A
B
C
D
A (XLR MICROPHONE INPUTS): Low impedance (resistance) , balanced microphone XLR input that
can also provide phantom power to a condenser microphone
Pin 1 : ground or shield
Pin 2 : Positive (+ or hot)
Pin 3 : Negative (- or cold)
B (1/4’’ LINE INPUTS): 1/4’’ input that can accept two different connections.
i) unbalanced/high impedance/TS (TIP/SLEEVE) connectors
ii) balanced/low impedance/TRS (TIP/RING/SLEEVE) connectors
C (LOW CUT switch): Cuts bass frequencies below 75Hz at a rate of 18dB per octave
D (TRIM): Adjusts the input sensitivity of the mic and line inputs.
i) XLR input can be boosted by 60 dB
ii) LINE input can be attenuated (brought down) by 15dB or boosted by 45 dB. “U” is when there
is no gain or attenuation to the signal
F
G
E
E (STEREO LINE INPUTS): Fully balanced inputs that are used for stereo or
mono, balanced or unbalanced signals. These are often used to hook up stereo
signals from keyboards, tape/CD/MP3 players and sometimes effects devices.
Odd channel = LEFT and Even channel =right.
F (AUX EFFECTS SEND/RETURNS) : Used to connects the inputs and outputs of
effects devices (reverb/delay/compressor/chorus etc..)
AUX 1 can be used for stereo or mono effect
AUX 2 can only be used for stereo effects
There is also an option of using the SEND Outputs on either AUX to feed the
signal to monitors instead of effects.
G (UNBALANCED RCA TAPE/CD/MP3 PLAYER INPUTS/OUTPUTS): Used to
hook up most types of audio players/recorders except for turntables. The
input signal is automatically boosted by 6 dB. The output line is used for
making a stereo recording (board mix) from the mixer’s main outputs.
H
I
H (1/4” MAIN OUTPUTS): This is one of Two Main Stereo Outputs. Either
unbalanced (TS) or balanced (TRS) 1/4’’ connectors can be used.
TIP (T): + (hot)
RING (R):
- (cold)
SLEEVE (S):
Ground
I (PHONES OUTPUT): Used for listening to mixer’s output with stereo
headphones with 1/4’’ (TRS) output.
Channel Strip
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This is the section of the mixer where basic
adjusts are made to the incoming signal such as:
effect level, equalization, panning, signal
routing, and volume level.
Most channel strips are used for an individual
microphone or a mono instrument line. Some
channel strips will accept stereo signals. Usually
those on the far right of the console.
AUX : Used to set the amount of signal that is
sent to an external processor or to monitors.
3 Band Parametric EQ :
Hi : Boost or cut frequencies around 12000 Hz
(12kHz) by 15dB
MID : Boost or cut frequencies around 2500 Hz
(2.5kHz) by 12dB
LOW : Boost or cut frequencies around 80 Hz by
15dB
PAN : Adjusts the amount of channel signal sent
to the left vs. right outputs.
Dual purpose MUTE/ALT 3-4 Switch: Will silence
the channel or send the signal from this channel
to the ALT 3-4 bus.
SOLO switch: Silences all other channels except
for this one.
CHANNEL FADER : Controls the channel level
from Unity Gain (U) up to 10 dB of boost or
down to oo
Master Section
This is the control centre of the mixing board.
a)
b)
c)
level adjustments are made: effects, stereo
output (L/R), ctr room/submix outputs (L/R).
meters and lights indicate: mixer power,
phantom power, rude solo light, VU meters.
signal routing options are chosen: pre/post
efx, efx to monitors, control room/submix
signal source.
J
K
L
J ( AUX 1 MASTER) : Provides overall control of signal that
is sent from the AUX SEND 1 output. AUX SEND 2 has no
output dial !
M
K (EFX TO MONITOR) : Used to send EFX from AUX SEND
2 into AUX SEND 1.
N
L (AUX RETURNS): Sets the amount of effect coming in
from the AUX RETURNS 1 and 2
O
M (AUX 1 SELECT) : Allows you to choose whether you
want to tap the signal that is to be effected either PREFADER/UP (most common when used for monitoring) or
POST-FADER/DOWN (usually only used for effects when
you want the “wet” signal to follow the “dry” signal).
P
N (CONTROL ROOM/SUBMIX MATRIX): Buttons that
allow the engineer to quickly route the MAIN MIX, ALT 34 selected channels, or the TAPE INPUTS to the Control
Room/SubMix/Phones Outputs. Any combination of these
may be chosen simultaneously.
O (ASSIGN TO MAIN MIX): Feeds the C-R/SOURCE
Selections into the MAIN MIX.
P (SOLO MODE) : This is used to set Pre-Fader Listen
(PFL) and After-Fader Listen (AFL) levels on the VU
Meters
Q (PHANTOM POWER AND MIXING BOARD POWER
LIGHTS): Allows the engineer to know when
phantom power or the mixer is itself is turn on.
R
Q
U
R (VU METERS): Displays volume units for specific
signals that are chosen in the C-R/SOURCE matrix
or soloed channels.
S (CONTROL ROOM/SUBMIX): Sets master level of
CONTROL ROOM/SUBMIX
T (MAIN MIX): Sets overall level of the MAIN MIX
U (RUDE SOLO LIGHT): This light reminds the
engineer if any of the channels are in solo mode.
S
T
Output Section
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This is the portion of the mixer where
different cables are patched in to feed the
signal to other sources. This could be:
power amplifiers, speakers, recording
devices, effects, headphones or other
mixers.
V
W X
Y
V (POWER CONNECTION and FUSE BOX): Internal power
supply that powers the mixer. Accepts a standard 3 prong
IEC power cord. Below is a compartment that houses a 0.5
amp fuse.
W (POWER SWITCH) : Turns mixer power on and off.
X (PHANTOM POWER SWITCH) : Turns phantom power
for condenser microphones on and off.
Y (XLR MAIN OUTPUTS): Left and Right XLR/low
impedance/ Balanced Output that are controlled by the
MAIN MIX fader.
Z
AA
BB
Z (MAIN OUTPUT LEVEL PAD): Lowers the signal
level from the MAIN OUTPUTS by 30 dB. This is
helpful when feeding the main mixer signal to
another mixer.
AA (1/4 ‘’ CONTROL ROOM OUTPUTS): Balanced or
unbalanced 1/4’’ output whose level is controlled
by the CONTROL ROOM/SUBMIX fader.
BB (1/4 ‘’ ALT OUTPUT): Balanced or unbalanced
1/4’’ output for any channels where the MUTE ALT
3-4 button is selected.
CC (CHANNEL INSERTS): Allows certain effects to
be connected to single channels using a TRS Insert
Cable . This is used most often for compressors,
filters, equalizers and de-essers.
CC