NAD 310 Manuel D'installation page 7

to the speaker terminals, being careful not to leave
any loose strands of wire that might touch the wrong
terminal and create a partial short-circuit. Then move
the speakers to their intended locations.
If the speakers cannot easily be set face-to-face,
phasing must rely on the "polarity" of the connecting
wires. Note that the SPEAKERS terminals on the
amplifier are color coded: in each channel the red
terminal has positive "+" polarity and the black termi-
nal is negative "-". The terminals at the rear of the
speakers are also marked for polarity, either via red
and black connectors or by labels: "+", 1, or 8 ohms
for positive, "-", 0, or G for negative. As a general
rule the positive (red) terminal on the amplifier should
be connected to the positive terminal of the speaker,
in each channel.
To facilitate this, the two conductors comprising the
speaker wire in each channel are different, either in
the color of the wire itself (copper vs. silver) or in the
presence of a small ridge or rib pattern on the insula-
tion of one conductor. Use this pattern to establish
consistent wiring to both speakers of a stereo pair.
Thus if you connect the copper colored wire (or
ribbed insulation) to the red amplifier terminal in the
Left channel, do the same in the Right channel. At
the other end of the wire, if you connect the copper
colored wire (or the ribbed insulation) to the red or
positive terminal on the left-channel speaker, do the
same at the right-channel speaker.
IN CASE OF DIFFICULTY: A TROUBLE-SHOOTING GUIDE
SYMPTOM
No sound.
No sound in one channel
Loud buzz and hum.
Hum in tape playback
Weak bass, diffuse stereo imaging
A note on overload protection.
Because NAD amplifiers sound so clean and musi-
cal when driven beyond their nominal power ratings
and when used to drive low-impedance loudspeak-
ers, you may be tempted to stress your amplifier
beyond its design capacity. It can safely and cleanly
drive complex speaker impedances with wide-range
musical signals whose peak level is 40 watts or more,
but it may overheat if called upon to deliver high
power CONTINUOUSLY into a low impedance.
Thus you may play music at volume levels that
cause the brief transient peaks and climaxes in music
to exceed the amplifier's rated power by a consider-
able margin. But if you overdrive the amplifier contin-
uously rather than only on peaks, the output transis-
tors may overheat.
This is particularly likely if you try to drive two pairs
of speakers, or speakers having a very low imped-
ance, at high volume levels. If the amplifier stops
playing and the "Protection" indicator glows red,
switch off the power for a few minutes and allow the
output stage to cool. If overheating was the fault, the
amplifier will operate normally when it is turned back
on. But severe abuse of this type may cause internal
fuses to blow to protect the amplifier. If the amplifier
stops playing and the green Power LED ceases to
glow, return the amplifier to a NAD dealer for service.
POSSIBLE CAUSE
Power not turned on.
AC line cord unplugged, or plugged into dead outlet. (To check the
AC outlet, plug in an electric lamp.)
Tuner selected but turned off or tuned to a blank frequency between
stations.
Inoperative input selected (e.g. CD input selected with no CD
playing).
Tape Monitor engaged with no tape playing.
Internal fuses blown; return amplifier to dealer for service.
Volume control for one of the channels is turned down. Check the
concentric volume control and ensure that both left and right are at
an equal level.
Loudspeaker connecting wire pulled loose. (Check all connections,
both at the speakers and at the amplifier.)
Connecting cable pulled loose or making poor contact in socket.
Rotate plugs in jacks to restore contact.
Short-circuit in a defective connecting cable. Wiggle all cables,
especially where they enter plugs.
Dirty contact in a switch. Exercise all front-panel switches to
restore clean wiping contact.
Connnecting cable pulled partially out of its jack.
Defective connecting cable.
Tape deck located too close to amplifier (directly above or below).
Tape deck located too close to television set.
Plugs making poor contact in jacks.
Speakers wired out of phase. Swap connections at the back of
ONE speaker.
GB
NAD
7