Plugging U P The System - ALLEN & HEATH MixWizard Series User Manual

P U
LUGGING P
The Mix Wizard 14:4:2+ uses professional grade 3-pin XLR, 1/4" TRS jack and RCA PHONO
sockets. The applications diagrams on pages 19 to 21 illustrate typical equipment
interconnections. To ensure best performance, we recommend that you use high quality audio
cables and connectors, and take time to check for reliable and accurate cable assembly. It is well
known that most audio system failures are due to faulty interconnecting leads.
C
ONNECTOR
C
ONNECTORS
All input and output XLR connectors are 3-wire differentially balanced. These have 3 connector
pins: pin 1 = ground (cable screen), pin 2 = signal +ve, pin 3 = signal -ve
All the master output jack connectors are 3-wire balanced. These have 3 connector pins: tip =
signal +ve, ring = signal -ve, sleeve = ground (cable screen).
Avoid reversing +ve and -ve on balanced connections as this will result in out of phase signals
(reverse polarity) causing signal cancellation effects. This situation is particularly common in multi-
microphone mixing.
For live work where long cables runs are required, balanced interconnections should be used.
Short interconnections between more affordable 2-wire (signal, ground) unbalanced effects units or
signal processors and mixing console may be utilised.
unbalanced to balanced connections.
D
EALING WITH
For optimum performance all audio signals should be referenced to a solid, noise-free earth point,
frequently referred to as the 'star point' or 'clean earth'.
A ground loop is created when the signal has more than one path to ground (earth). Should you
experience hum or buzz caused by ground loops, check first that each piece of equipment has its
own separate path to ground. If so, operate ground lift switches on connected equipment in
accordance with the instruction manuals.
destination end.
To avoid interference pickup keep audio cables away from mains power units and cables, thyristor
dimmer units or computer equipment. Where this cannot be avoided, cross the cables at right
angles to minimise interference.
C
ONNECTING
Both microphone and line sources such as keyboards, replay devices and effects processors can
be plugged into either the jack or XLR input for convenience. Do not connect to both at the same
time. The channel accepts a wide 70dB range of source levels. The balanced 3-wire input
provides the best immunity to interference pickup on long cable runs.
WZ14:4:2+ U G
SER UIDE
T S
HE YSTEM
P
INOUTS
, C T
ABLES AND HEORY
G L , B
ROUND OOPS UZZ AND
C I
HANNEL NPUTS
Refer to the following diagram for
I
NTERFERENCE
Alternatively disconnect the cable screen at the
11