Cloud Electronics 44/50 - Manual (Page 7)

6 44/50: Installation and Operation Manual
15 High Pass Filter
Both microphone channels pass through independent 3 pole high pass filters operating at
100Hz that provide effective attenuation of breath blasts and LF handling noises at a rate
of 18dB/octave. The circuitry providing this feature is fixed and cannot be defeated.
16 Microphone Level Controls
Separate front panel mounted level controls for Mic 1 and Mic 2 are provided for each of
the four zones. The level controls provide the user with a convenient means to operate
either microphone at a suitable level in any zone; rotating any mic level control to the fully
anti-clockwise position effectively turns the microphone off.
The microphone signals are routed directly to the power amplifier stage of the respective
zone and mic signals are totally unaffected by the operation of the music controls. The
Mic 1 & Mic 2 gain controls on the rear panel should be set at a level where it is not
possible to have excessive gain even when the front panel level controls are fully
clockwise.
For the benefit of the operator, self-adhesive labels are provided to identify the
microphone channels and these can be fixed on the 44/50 front panel in the space
provided, below and to the right of the power switch.
17 Microphone Priority
Fully automatic, voice operated priority is provided so that when a microphone is used,
the music signals will attenuate by approximately 30dB; after the announcement, the
music signals will restore smoothly to their former level. This ‘microphone over music’
priority can be defeated by configuring the internal jumper J10 located on the
motherboard. Microphone priority is also provided and this allows announcements on the
Mic 1 channel to have priority over any signal present on the Mic 2 channel, if you wish to
disable this Mic 1 over Mic 2 priority then remove R160 from the 44/50 motherboard.
18 Auxiliary Outputs
Line level auxiliary outputs are provided to satisfy the occasional requirement to connect
additional power amplifiers to any of the four zones, which may require more than the 50
watts provided. RCA type phono sockets mounted on the rear panel provide an output
level of 0dBu (775mV) which should interface optimally with most types of power
amplifier. If this auxiliary output signal is terminated to a balanced input stage, please
remember to follow the manufacturers recommended procedure to unbalance the input
stage. To reduce the risk of creating a ‘ground loop’, the additional power amplifier(s)
should be positioned close to the 44/50 and be connected to mains power sockets that
are on the same circuit.
19 Output Details
Binding posts for the four speaker outputs are provided on the rear panel these can
accommodate flexible leads up to 2.5mm². The output connectors are not compatible with
4mm ‘banana’ plugs. Do not make any connections to the unit with the power cable
attached and please remember that it is good practice to distance the output wiring from
the input wiring and also use twisted pair cable for the speaker wiring.
20 100V or 70V Line Operation
The CXL-400 four-channel line transformer module is available as an accessory to the
44/50. It is rated at 40 watts per channel and optimally matches the Cloud 44/50 power
amplifiers. The module is designed to fit inside the 44/50 chassis and may be configured
for 70 or 100V operation by means of wire links on the PCB. Unless specified otherwise,