NAD 2600 - REAR PANEL CONNECTIONS; AC LINE CORD; AC LINE FUSE; SPEAKER IMPEDANCE

A NOTE ON INSTALLATION
This unit may be installed on any sturdy, level surface.
Since its power transformer generates a magnetic hum field
of
moderate
strength,
a
turntable
(especially
one
with
a
moving-coil pickup cartridge) should not be located directly
to the left of the amplifier nor directly above it.
The amplifier generates a modest amount of heat and
thus
requires
some
ventilation.
Do
not
place
it
on
a
rug
or
other soft surface that it could sink into, obstructing the air
inlets
on
its
bottom.
And
be
careful
not
to
obstruct
the
air
outlet grille on the top cover.
CAUTION: To prevent a fire or shock hazard, do not
permit liquid or moisture to enter the amplifier. If liquid is
accidentally spilled on it, immediately shut off its power and
unplug its AC power cord. Allow sufficient time for complete
evaporation to occur before operating the amplifier again. (If
the liquid is anything but water and/or alcohol, the amplifier
should be examined by a service technician before power is
applied to it.)
Do not open the amplifier, or attempt to modify or repair
it yourself. Refer all servicing to a qualified technician.
REAR PANEL CONNECTIONS
1. AC LINE CORD
Plug the AC line cord into a nearby wall outlet that
provides the correct AC power line voltage.
If you must use an AC extension cord, it should be
a heavy-duty (14 or 16 gauge) cord.
You may plug the power amplifier into a “switched” AC
outlet on your preamplifier, and use the preamp’s Power
switch to turn the entire system on and off. But this is
recommended ONLY IF the preamp’s AC switching is rated
to handle this amplifier’s maximum power consumption (700
watts). The preamplifier’s power switch should be rated to
handle a turn-on surge current of at least 10 amperes.
If your preamplifier was not designed for high-current
power switching, the practical alternative is to connect the
preamp and power amp to a “power strip” containing several
AC outlets, and use its heavy-duty switch to turn your system
on and off.
2. AC LINE FUSE (Only in 220V, 240V Models)
Prolonged operation at excessively high power levels
could cause this line fuse to blow. If this occurs, the amplifier
will not operate, and the Power LED on the front panel will
remain dark. In this case, unscrew the fuse holder and install
anew 5-ampere fuse. If the second fuse blows, return the
amplifier for service.
3. SPEAKER IMPEDANCE
The impedance of a loudspeaker varies with frequency,
and in many loudspeakers the impedance is lowest at the
frequencies where the highest power demands occur in
music. In many “8Q” loudspeakers this minimum impedance
is from 4 to 6 ohms. And if you connect two pairs of 8-ohm
speakers to the amplifier the nominal impedance of the
combination is 4 ohms.
For these reasons, all NAD amplifiers and receivers are
designed to produce maximum power output into a 4-ohm
impedance, and 4Q is the Normal setting of the Impedance
selector. If you are not sure of the true impedance of your
speakers, leave the Impedance switch at 40 (NORMAL).
If you are using a single pair of loudspeakers whose
impedance is 8 ohms or higher, you can optimise the
amplifier for maximum power delivery at this higher imped-
ance by re-setting the switch to 8Q (HIGH).
NOTE: The power must be switched off whenever
the Impedance switch is operated (reset from 8 to 4 or
vice versa).
To prevent accidental re-setting, the impedance switch
is recessed within a slot in the rear panel. Use the tip of
a small screwdriver to slide the switch down to the 8Q
(HIGH) position.
CAUTION: If the impedance switch is set to 8Q (HIGH)
with loudspeakers whose true impedance is lower than 6
ohms, or with two pairs of speakers connected in parallel, the
amplifier will tend to overheat and shut down when operated
at high output levels. The amplifier will resume normal
operation after it cools; but such abuse could also cause
internal fuses to blow in order to protect the amplifier. if this
occurs, return the amplifier to your dealer for service.
4. SOFT CLIPPING
When an amplifier is overdriven beyond its specified
. power output it normally produces “hard clipping” of the
signal with harsh distortion and power-supply buzz as the
output transistors saturate. The NAD Soft Clipping circuit
gently limits the output waveform and minimizes audible
distortion when the amplifier is overdriven. If your listening
involves moderate peak power levels, the Soft Clipping may