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Plug
the signal cables from your turntable
into
these
jacks.
lf
the cables or
plugs are
color-coded,
refer to
your
turntable's instruction
manual
to
learn which
cable or
plug
is
for the Left channel
and
which
is
for the
Right. Be
carelul
to
insert each
plug
fully
into
the socket
so
that the
plug's metal
skirt fits tightly over the
exterior
of the socket. lf
necessary,
crimp
the
leaves
of the
plug's metal
skirt slightly
inward so
as
to obtain
a
tight fit
with
the
socket.
Moving-coil pickups with
low output
voltage should
be
used
with
an external
transformer or pre-preamp.
Plug the
turntable's cables
into
the
input
jacks of the step-up
device,
then
connect
its outputs to
the
PHONO jacks.
3.
PHONO
GROUND.
lf
your turntable
is equipped
with
a
grounding wire
(usually a green wire
terminating
in
a
U-shaped spade
lug),
connect
it to
this
screw terminal.
Use a
screwdriver to
loosen
the
screw, place
the spade
lug
under
the
head
of the
screw, and
tighten the
screw clock-
wise
to
secure
the lug. lf
the
grounding wire has
no
terminal
lug,
strip
off a
half-inch
(1
to
2
cm) of insulation to
expose
the
bare
wire, twist the
wire
strands tightly
together, and
fasten the
bare
wire
under
the
head
of the Ground
screw.
CAUTION:
Do not use excessive
force
when
tightening
the Ground
screw,
or you
may strip
the
threads.
4.
AUX INPUT. These
auxiliary
jacks
are
for
any
"line
level" signal source, such
as
a
television
sound tuner, the
audio line output
from
a
videocassette
or
videodisc
player,
or the decoded signal from
a
digital
audio
disc
player. As
with
the other input/output jacks
on
this
receiver,
the
upper
jack
in
each pair
is
for the Left channel
and
the
lower
jack
is
for the
Right channel.
5.
TAPE RECORD/PLAY.
The tape connections
may be used
with recorders of
all
types: cassette,
micro-
cassette, open-reel, digital, etc.
To
play recorded tapes,
connect
a
stereo
patch cord
from the recorder's
LINE OUT
jacks
to
the receiver's
PLAY
input
jacks.
To
make record-
ings,
connect
a
stereo
patch cord
from the receiver's
RE-
CORD
jacks
to
the recorder's LINE
lN
jacks
(not
to
its
microphone
inputs).
lf
you wish to
use a
signal-processing accessory
with
your
receiver-such
as a
graphic
equalizer, a dynamic
expander,
a
DBX
or
CX disc decoder, a noise filter,
or
an
ambience-reproduction
system-you
must
connect
it
to the
receiver's
TAPE RECORD/PLAY
iacks.
Disconnect the
tape
recorder,
connect
a
cable
from
the receiver's
RECORD
output
jacks
to
the processor's "From Amplifier"
main in-
puts, and
connect another
cable
from the processor's
"To
Amplifier" or "Monitor
Output"
jacks to the receiver's
PLAY
inputs.
Then connect your tape recorder
to
the
signal
processor's
own TAPE RECORD/PLAY !acks.
6.
DC
OUTPUT
This DIN-type
socket
can
provide op-
erating power
(+
17
volts
DC)
to certain accessory
products
such
as a
pre-preamplifier for
low-output moving-coil car-
tridges. Such products
might have
to
be
fitted with
a plug
that
fits
this
socket.
7. SPEAKERS.
lf
the wiring to each
loudspeaker
will
not
be longer than
about 6
meters
(20
feet),
then
connections should
be made using 18-gauge
wire such
as
common
lamp
cord ("zip" cord),
available
from
hardware
and
e]ectrical-supply stores
in either
white,
black,
or
brown
insulation.
lf
the
wiring
to the
speakers will
be
longer
than
about
6 meters, heavier
16-gauge
or
14-gauge
wire
is
preferred.
Heavy-duty
wiring
is
especially desirable
if
you are
using
speakers of
low
impedance or two
pairs
of
speakers wired
in parallel.
To
make
connections, separate
the
two conductors
of
the cord,
strip off about a
half-inch
(1
cm)
of
insulation from
each,
and
in each
conductor twist together the
exposed
wire
strands.
Fully
depress the
colored
tab
below each SPEAK-
ERS
terminal
in
order to open
up
the
hole in the terminal,
then insert the
bared
wire
into
the
hole
and
release the tab;
the
terminal will
grasp the
wire and
hold it in
place.
Repeat
for each
conductor,
connecting
the wires
from the left-chan-
nel
speaker
to
the
L+
and
L-
terminals
and the
wires
from
the right-channel speaker
to
the
R
+
and
R
-
terminals.
Check
to
be sure
that
no loose
strands
of wire are
touching
any
adjacent terminal
or wire.
PHASING.
Stereo speakers should operate
in phase
with each other
in
order
to
yield
a
good stereo
image and
to reinforce rather than cancel
each
other's
output at low
frequencies.
lf
your speakers
are
easily
moved, phasing can
easily
be
checked.
Make
the connections
to
the
speakers,
place
the speakers
face-to{ace
only
a
lew inches
apart,
play
some music, and
listen.
Then
swap
the connection
of
the
two wires at the
back
of
ONE
of the
speakers,
and
listen
again.
The connection which produces
the
fullest,
boomiest
bass
output
is
the correct one.
Connect
the wires
securely to
the speaker terminals,
being
careful to avoid
leaving loose
strands
of wire
which
might
touch
the
wrong terminal
and
create
a partial short-circuit,
and
then
move
the
speakers
to
their intended
locations.
lf the speakers
cannot
easily
be set
face-to{ace,
then
phasing must
rely on
the "polarity" oI
the
connecting
wires.
Note
that the
SPEAKERS
terminals
on
the receiver
are
color-coded:
in each
channel
the
terminal
with
the
red tab
has
positive
"
+
" polarity
and
the
black
terminal
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 receiver
is
to
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 insulation of
one
con-
ductor. 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
receiver termi-
nal 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.
8.
SPEAKER IMPEDANCE. The impedance
of a loud-
speaker varies
with frequency,
and in
many loudspeakers
the impedance is lowest
at the
frequencies where the
high-
est
power
demands occur
in
music.
ln
the
majority
of
"8
ohm" loudspeakers this minimum impedance
is from 4
to
6
ohms, and
in
"4 ohm"
speakers
the minimum
is
typically
3
ohms.
And
if
you were to connect two
pairs of speakers to
the
receiver,
wiring them
in
parallel, their combined
imped-
ance
would
be
approximately half the
impedance of either.
For
these reasons, all
NAD receivers are
designed
to
produce maximum
power
output into
impedances of 2
to
6
ohms. But
the
7120
receiver
is
equipped with
a Speaker
lmpedance selector which you can
re-set
to
increase the
available
power
output
into 8
ohms and higher
impedances.
lf
you are
not sure
of
the
true
impedance of
your
speakers,
or
if
you are connecting two pairs ol speakers,
leave the
lmpedance switch in its NORMAL
(4 OHMS) setting.
ll you are
using a
single
pair
of
loudspeakers whose
minimum impedance
is
at
least 6
ohms
and
whose
average
impedance
is
above
8 ohms,
you should
re-set this
switch
to
re-optimise the amplifier for maximum
power
delivery
at this
higher
impedance.
First,
turn
down
the
Volume
or
switch off
the
Power.
Now, in
order to prevent the lmpedance switch from
being
re-set
accidentally, it
is
held
tightly
in place by a pair of
screws
located
to the left and
right
of the switch handle.
Use
a
screwdriver to
turn
the
screws
slightly
counter-clockwise
to loosen them.
(DO
NOT
REMOVE the
screws!)
Note
that
the screws
are
installed
in
slots
so
that they can
be moved
to
the left or
right.
To
set the lmpedance selector to
HIGH
(8
OHMS),
slide
the screw
heads all the way to
the left
end
of their respective slots. Then re-tighten the
screws.
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