Instruction manual
,q-
S'VlSTEM 1
~ E
PEA
T
WIRtN
G
AS FOR SYSTEM 1
contained playback preamplifiers. phono cartridges
with
RIAA-equalized high-level
output,
additional
tuners and/or receivers,
TV
sound outputs, and
other external components.
aUADRADIAL
In anticipation
of
the coming
of
4-channel stereo
broadcasting,
your
Model 2270 is equipped
with
an
output
aUADRADIAL
jack. The signal avai-
lable at this jack is the unequalized, buffered
output
of
the FM discriminator. Its level, fre-
quency
response
characteristic and
output
im-
pedance are ideal to drive any 4-channel adaptor.
This jack can also be
used
as a simple white
noise generator
for
frequency response check
of
loudspeakers or amplifiers
with
the Model
2270 in FM mode and tuned
off
from any FM signal.
MAIN
IN and PRE
OUT
The inter-connections from the Model 2270 on
the preamplifiers outputs to the power ampli-
fiers inputs are performed externally. Special
jumper plugs normally interconnect these
MAIN
IN and PRE
OUT
jacks. Removing these
two
special jumper plugs allows you
to
use
your
2270 as an independent basic stereo amplifier
and/or an independent stereo control center. Be
sure
to
replace the jumper plugs between the
MAIN
11\1
and PRE
OUT
jacks
for
normal operation.
3
Figure
2. loudspeaker
System
Connections
LOUDSPEAKER SYSTEMS
The SPEAKER SYSTEMS terminals on the rear
panel
will
accomodate
two
stereo pairs
of
loud-
speaker systems
of
rated impedance between 4
ohms and 16 ohms. When using only one stereo
pair
of
loudspeakers, connect them to the
MAIN
terminals. The REMOTE terminals are
for
a
second stereo pair
of
loudspeakers.
Selection
of
loudspeaker systems is made
with
the MAIN-SPKR-REMOTE pushswitches on the
front
panel.
Use caution when connecting
your
Model 2270
to a loudspeaker
with
built
-in power supply such
as an electrostatic loudspeaker. The
"common"
connection terminal
of
such a speaker may be
capacitively grounded through its power supply.
Make sure the
GROUND
terminals
of
the Model
2270 are connected to the
"common"
terminals
of
such loudspeaker systems.
Ordinary
# l8-gauge, 2-conductor lamp cord ("zip-
cord")
may be used
for
normal
distances (to about
25 feet) between
your
2270 Receiver and your
loudspeakers.
For
longer lengths,
#16
-gauge
or
heavier wire should be used
to
ensure optimum
speaker performance.
When connecting a stereo pair
of
loudspeakers,
it
is
important
to
ensure correct relative phasing
(polarity). When using identical loudspeakers, sim-
ply
code one wire
of
each pair at both ends
with
a knot, tape, etc. (Note: Close inspection
of
stan-