WZ
3
20S
User Guide
29
AUX master balance option
The 6 aux
outputs are impedance balanced as standard
operating at nominal -2dBu and with +21dBu
maximum drive. They provide similar interference
rejection to electronically balanced outputs when
connected to balanced equipment inputs. An
electronically balanced option is available if you
require n4dBu and higher output drive up to
+26dBu over very long cable runs. However, it is not
usually necessary to fit this option as the impedance
balanced drive satisfies most applications. Check
that you really need the option before fitting it.
There are two balanced driver ICs which may be
used. Either is suitable. These are available from
Allen & Heath or most electronic component
suppliers. The Allen & Heath part number is shown
below:
SSM2142P
A&H Part AE0302
DRV134
A&H
Part
AE5725
For each aux master, snip the legs of the two zero
ohm resistor links as shown. This removes them
from the circuit. Now simply plug the option IC into
the socket. Observe the correct IC pin1 orientation
and make sure its legs are correctly aligned with the
socket. Test the output once the work is complete.
You should measure the same level but opposite
polarity signal b (hot) and ground, and –
(cold) and ground.
Sys-Link II output option
A blank plate is
fitted here as standard. This may be replaced with
an optional card which provides a 37way D
connector for linking the outputs to other Allen &
Heath consoles already fitted with Sys-Link II. The
WZ
3
20S
can become input channel expanders for
other consoles.
IMPORTANT:
The option does not include the Sys-
Link II input. Therefore the
WZ
3
20S
cannot be used
as the master in a linked system, nor can two of
these models be linked together. You need to
connect these to a console that does include the
Sys-Link II input connection, for example the
WZ
3
14:4:2
or
ML3000
with the option already fitted.
Also note that you need an adapter cable if you are
connecting Sys-Link II (Version 2) to the older Sys-
Link I (Version 1) standard.
A 37way shielded multi-core cable carries the
MixWizard balanced mix signals and PFL system to
the master console.
For full details please refer to the Sys-Link option
Applications Note AP5736 and Fitting Instructions
AP5735.
AUX MASTER - BALANCED OUTPUT OPTION
U12
U11
U10
U9
U8
U7
AUX6
AUX5
AUX4
AUX3
AUX2
AUX1
CUT OUT 2x 0 OHM RESISTOR LINKS
PLUG IN SSM2142 or DRV134 IC
1
SLAVE CONSOLE
SYS-LINK II OUTPUT
WZ320S
SYS-LINK II INPUT
WZ314:4:2 OR OTHER A&H CONSOLE
SYS-LINK II OUTPUT
MASTER CONSOLE
37WAY CABLE