5
OUTPUT CONNECTIONS
EMX1A outputs are electronically balanced auto compensating via male
XLR type connectors. Pin 1 is the (ground) connection and the signal
appears between Pins 2 and 3.
Always use 2-core + screen ‘balanced’ type signal leads, even for
unbalanced circuits. The screen should be regarded as separate from the
signal return, even if they are connected together at one end of the line.
This is to keep the screen a true screen so that no signal return currents
flow through it which can induce signals in adjacent cables.
For unbalanced use, having decided which pin is ‘hot’ (see above), connect
the ‘cold’ pin and (Pin 1) together. The internal signal ground lead should
be placed in the earth off position at the EMX1A outputs which permit the
amplifier to be locally grounded (as required for safety reasons) without
causing a hum loop. If the signal is merely taken between either Pin 2 or 3
and Pin 1, a level loss and signal degradation will occur.
For balanced operation, the screen should be connected to ground at the
amplifier end. To eliminate ground current loops, it can be lifted at the
EMX1A output, provided normal safety requirements have been met (ie the
mains earths are correctly connected).
The power ratings of amplifiers connected to EMX Series controllers should
lie within the range recommended for the EM Series loudspeaker system
being driven. Please refer to the section on amplification in the EM Series
user’s guide for further information.
6
MODES OF OPERATION
The EMX1A is a 2-channel system controller which is recommended for
use with the Martin Audio EM passive loudspeaker systems used either full-
range or with additional Martin EM201, EM251, EM150 or EM120 sub-bass
systems.
In its full-range mode, the EMX1A provides full system equalisation as well
as loudspeaker protection using limiters activated by the true voltages
applied to the loudspeaker. In its sub-bass mode, it is reconfigured
automatically as a 2-in/4-out, 120Hz electronic crossover which provides
2 x sub-bass and 2 x full-range/high-pass outputs. All four outputs are
provided with sense inputs to monitor loudspeaker voltages.
Sub-bass or full-range mode of operation is selected by a push switch on
the front panel of the EMX1A and indicated by front panel LED’s. It is
important to note that the sub-bass outputs are always present at the sub-
bass output connector, even when full-range operation is selected for the
main system.
Martin Audio – EMX1A System Controller
E
NGLISH
4
CONTENTS
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GUIDES
