NAD 218 THX Manual Del Usuario página 7

times the Protection mode may be activated by
severe overheating, short-circuited speaker wiring, or
an internal fault.
If the Status light continues to glow red, switch the
Power OFF. When the output stage cools, relays will
automatically re-connect the speakers, and normal
operation can be resumed. In most cases a very
slight reduction in volume level will prevent further
interruptions.
If the protection relays interrupt the sound frequent-
ly, several possible causes should be considered: a
loose strand of wire causing a partial short-circuit
between speaker terminals, or continuous high-power
operation into a very low impedance in the Bridged
mode, or any obstruction of the free flow of air that is
needed to ventilate the amplifier and dissipate its
heat.
If the protection system interrupts the sound even
when the amplifier is cool, return the amplifier to your
NAD dealer for service. The protection relays may be
IN CASE OF DIFFICULTY:
A TROUBLE-SHOOTING GUIDE
PROBLEM CAUSE
No sound.
Power not on. AC line cord unplugged, either at the wall
or at the rear of the amplifier.
No sound in Speaker cable pulled loose.
one channel.
Input cable pulled loose or making poor
contact in socket.
Short-circuit or broken wire in a defective
input cable.
Weak bass; Loudspeakers wired out of phase.
poor stereo imaging.
Bridging switch set to ON (MONO) while
speakers are connected for stereo
operation.
disengaging to protect your speakers from a circuit
fault, such as an improper DC voltage at the speaker
terminals.
3. BRIDGE MODE INDICATOR.
This amber LED glows when the Bridging switch is
set to ON (Mono).
4. SOFT CLIPPING INDICATOR.
This amber LED glows when the Soft Clipping
switch (on the rear panel) is ON.
REMEDY
The Protection mode has been engaged
to protect the amplifier from short-circuit
ed speaker wires or from overheating
caused by overdriving the amplifier into
a too low impedance To resume opera
tion, switch the Power OFF and allow
the amplifier to cool.
Check all connections, both at the
speakers and at the amplifier.
Rotate RCA phono plugs in input sock-
ets to restore good contact.
Wiggle cables, especially where they
enter plugs (at the preamp and at the
amplifier).
Swap connections at the back of ONE
speaker.
Re-set the Bridging switch to OFF
(STEREO).
GB
NAD
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