User manual

6
EMS-81X User Manual
www.emacoustics.co.uk
personnel following safe working practice. Should you be in any doubt whatsoever, please contact
your local dealer who will be able to refer you to a suitable rigging company.
Cabling and Amplifier Selection
The EMS-81X is designed to be used with professional power amplifiers providing the following power outputs:
EMS-81X 500W/channel into eight ohms
It is good practice to use an amplifier equal to the program power rating of the loudspeaker – so as to retain
sufficient headroom and good dynamic range. Care should be taken during operation to avoid amplifier clipping –
as this can cause serious damage to your loudspeakers. If in doubt, please contact your dealer who will be happy
to assist you in correct amplifier choice and setup.
Cabling
The EMS-81X is supplied as standard with Neutrik SpeakON
TM
NL4 connectors, wired pin 1+/1-. It is
recommended that the resistance of your cable is less than one tenth of the nominal system impedance. Given
below are the recommended maximum cable lengths for different cross-sections and impedances.
Conductor Cross Sectional Area Maximum Recommended Cable Length
4 ohms 8 ohms 16 ohms
1.0mm
2
11m 22m 44m
1.5mm
2
17m 34m 68m
2.0mm
2
22m 44m 88m
2.5mm
2
29m 58m 116m
4.0mm
2
44m 88m 176m
6.0mm
2
66m 132m 264m
Pins 2+/2- on the SpeakON
TM
connectors are wired together to allow link-through with 4-core cables.
A small power amplifier working too hard is more likely to damage a loudspeaker than a large power amplifier
working within its operating range!