10
WZ14:4:2
U
SER
G
UIDE
P
LUGGING
U
P
T
HE
S
YSTEM
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 5 to 7 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
P
INOUTS
C
ONNECTORS
,
C
ABLES AND
T
HEORY
All input and output
XLR
connectors are 3-wire differentially balanced. These have 3
connector pins: pin 1 = ground (cable screen), pin 2 = ve, pin 3 = signal -ve
All the master output
jack
connectors are 3-wire balanced. These have 3 connector pins: tip
= ve, ring = signal -ve, sleeve = ground (cable screen).
Avoid revve 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. Refer to the following
diagram for unbalanced to balanced connections.
D
EALING WITH
G
ROUND
L
OOPS
,
B
UZZ AND
I
NTERFERENCE
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. Alternatively disconnect
the cable screen at the 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
C
HANNEL
I
NPUTS
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.
