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OPERATING PRECAUTIONS
Make sure the power switch is "OFF" before making any input or output
connections, installing a plug in module or operating any switches behind
the removable panel / plug in module.
Make sure that the AC mains are correct and that it is the same as that
printed on the back of the amplifier. See pages 11 & 12 regarding operating
voltage and power consumption.
It is always a good idea to turn down the gain controls during power up as
this prevents loudspeaker damage, especially if there is a high level signal
present at the input.
Powering Up
When the amplifier is first switched on the power "ON" and "max" LED’s
illuminates, it then takes a couple of seconds to self-check. If everything is
OK the "max" LED’s will extinguish and the power LED will stay "ON". This
is known as the "soft start" or "slow start" sequence, the fans then start and
the power amplifier is operational.
Input Attenuators
The two input level attenuators on the front panel adjust the signal level to
the respective amplifier channels. In bridged mode, only Channel A level
control is used.
Gain Switch
The gain switch (SW3) is located behind the plug in panel / module on the
front of the amplifier, when in the "OUT" position the gain of the amplifier is
36dB (input sensitivity 0.775Vrms), when in the "IN" position the gain of the
amplifier is 32 dB (input sensitivity 1.23Vrms).
When in bridge mode the amplifier sensitivity will remain the same in each
position of SW3, but the effective output gain will increase by 6dB’s in each
case, from 36dB to 42dB and from 32dB to 38dB. Most professional mixing
consoles operate at a nominal level of +4dBu. Therefore use the 32dB
position (SW3 switch IN). On MI or semi professional equipment that
operates at a nominal 0dBu level use the 36dB-gain setting (SW3 switch
OUT).
Indicators
The two bottom green LED's act as signal present indicators and operate
when the output signal is greater than -30dB's.
The yellow -3dB LED's indicate when approximately half of the power
capacity of the amplifier is being utilised.
The red "max" LED's indicate when the full capacity of the amplifier is being
used. Protection circuits within the amplifier allow the maximum output of
Martin Audio – E1300 Amplifier
E
NGLISH
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All material © 2007. Martin Audio Ltd. Subject to change without notice.
