www.redbackaudio.com.au
Redback® Proudly Made In Australia
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Redback® A 4235A/45A/55A
PA Mixer Amplifiers
Operating Manual
A 4235A
30W Mixer Public Address Amplifier
A 4245A
60W Mixer Public Address Amplifier
A 4255A
100W Mixer Public Address Amplifier
OVERVIEW
These compact 1RU rack mount ampliers are suitable for both stand alone PA system use, or as zone amplifiers in
larger systems requiring local inputs. All models operate on 240V ac or 24V dc for battery backup operation.
All models include a choice of six source options on 2 inputs. Input one consists of a 3-pin XLR which can be set for either
balanced mic level (3mV) or balanced line level (2V), adjusted via a rear mounted trimpot. A dual RCA is also provided
on input one with adjustable sensitivity of either 300mV or 1V. Input two consists of three sets of dual RCA sockets
on the rear panel and a 3.5mm jack on the front panel. Auxiliary source inputs are selected via the front panel switch.
Input one can be DIP switch selectable to VOX mute input two. Phantom power is also provided on input one XLR.
Volume level controls are provided on the front panel for inputs one and two.
The circuit includes protection features in case of output over voltage, over current and over temperature. All are self re-
setting once the fault condition is removed. Visual indication via front panel LEDs display amplifier status at all times.
FEATURES
• Compact 1RU 19” rack mount design
• Balanced mic or line input
• VOX muting
• Phantom power
• Four auxiliary inputs
• 3.5mm Jack Input (Front Mounted)
• Overload limiting
• Over voltage limiting
• On demand fan cooling (60W and 100W versions only)
• Over temperature shut down protection
• Dual input connectors
• Variable input sensitivities
• 240V ac / 24V dc operation
• Australian designed & manufactured
