Protection Features - Martin Audio E1300 Manual

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CONTENTS PRINT
GUIDES
the amplifier to be used without severe hard clipping.
The "card enable" LED indicates when a dedicated processing module is
fitted in the amplifier.
The remaining red "thermal" LED indicates the temperature status of the
amplifier. The E1300 is fitted with a sophisticated thermal management
system. Under normal operation the thermal LED will be "OFF", if more
power is demanded from the amplifier, or airflow to the amplifier is
restricted the LED will start to flash to indicate an elevation in operating
temperature. If no action is taken at this point the third status level will be
reached, the thermal and limit LED's will be "ON", and the amplifier will
protect itself by reducing the power to the load. When the amplifier has
cooled sufficiently the power will ramp back up to the previous level. If the
amplifier does not cool enough or the fans fail completely, the amplifier will
lock in a reduced power state until the problem is cleared.
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PROTECTION FEATURES

Every Martin Audio E series amplifier has many advanced protection
features that will protect both the amplifier and the loudspeakers connected
to it, should a fault condition arise. Under normal use these features are
inaudible.
Output Power Limiter
An output limiter is included to avoid severe amplifier clipping. When an
amplifier is severely overdriven, its output waveform is clipped (its peaks
are squared off) - reducing the crest factor. In extreme cases, the waveform
can approach that of a square wave. An amplifier is capable of producing
far more power under these conditions than its normal undistorted rated
power output. If the distortion exceeds 1% THD for any reason the limiter
reduces the input signal proportionally. Note that, if the input signal is
clipped before it reaches the amplifier, the clip limiter will not be
activated and severe damage to the loudspeakers could occur.
Amplifier Thermal Protection
All high power amplifiers produce considerable heat as a product of power
output. The E1300 is equipped with a very efficient heat exchanger and an
automatic logic controlled thermal management system.
When the amplifier is switched on the dual fans will start up and remain at
a low idling speed. As the amplifier provides more power the fans may
switch to the second cooling level. Under sustained demand for high power
or when there is insufficient cooling, the third level of fan speed is reached
and the red "thermal" LED on the front panel will begin to flash.
If no action is taken to either reduce the power demand or increase the
airflow through the amplifier, it will automatically protect itself, by reducing
the power to the loudspeaker. The status of the "thermal" and "max" LED's
will change to permanently "ON" and the green and amber signal LED's will
extinguish.
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All material © 2007. Martin Audio Ltd. Subject to change without notice.
Martin Audio – E1300 Amplifier