NAD C270 Manuel D'installation page 5

5. SPEAKERS A & SPEAKERS B
The NAD C270 is equipped with two sets of speaker connectors
wired in parallel to facilitate connection of multiple pairs of
speakers or "Bi-Wiring". Use the Speakers A connectors for the
'main' speakers and use the Speakers B connectors for a second
pair, for example, extension speakers located in another room.
Under normal operation, connect the right speaker to the
terminals market 'R +' and 'R-' ensuring that the 'R+' is
connected to the '+' terminal on your loudspeaker and the 'R-'
is connected to the loudspeaker's '-' terminal. Connect the
terminals marked 'L+' and 'L-' to the left speaker in the same way.
In Bridge Mode, connect the single speaker to the terminals
marked 'R +' and 'L+' ensuring that the 'L+' is connected to the
'+' terminal on your loudspeaker and the R+ is connected to the
loudspeaker's '-' terminal. Refer also to section "Bridge Mode" in
this chapter (No. 6).
Always use heavy duty (16 gauge; 1.5mm, or thicker) stranded wire
to connect loudspeakers to your NAD C270. The high-current binding
post terminals can be used as a screw terminal for cables terminating
in spade or pin sockets or for cables with bare wire ends.
BARE WIRES AND PIN CONNECTORS
Bare wires and pin sockets should be inserted into the hole in the
shaft of the terminal. Unscrew the speaker terminal's plastic
bushing until the hole in the screw shaft is revealed. Insert the pin
or bare cable end into the hole and secure the cable by tightening
down the terminal's bushing. Ensure bare wire from the speaker
cables does not touch the back panel or another socket . Ensure
that there is only 1/2" (1cm) of bare cable or pin and no loose
strands of speakers wire.
NOTE: Make sure the speaker impedance is 4 ohms or more
when connecting only one pair of speakers; make sure the
speaker impedance for all speakers is over 8 ohms when
connecting two sets of speakers. In Bridge Mode, the impedance
of the loudspeaker should also be 8 ohms or higher.
Always turn the C270 and other components in the system off
before connecting or disconnecting speakers.
6. BRIDGE MODE
The stereo NAD C270 power amplifier can be configured to be
mono (Bridge Mode), more than doubling its output power: 2 x
120 vs. 1 x 300 Watt. This way, the NAD C270 can be used as part
of a high power stereo or home-theatre system, by connecting
adding additional power amplifiers.
Set the BRIDGE MODE switch to the "Bridge" position and
connect the speaker to the terminals marked 'L +' and 'R+'
ensuring that the 'L+' is connected to the '+' terminal on your
loudspeaker and the 'R+' is connected to the loudspeaker's '-'
terminal. Connect the source to the Left MAIN-IN input.
In Bridged Mode the NAD C270 will produce approximately 300W
into an 8 ohm loudspeaker. In this mode, the amplifier sections
will react as though the speaker impedance has been halved. Low
impedance speakers (under 8 ohms) are not recommended when
using Bridge Mode, as these may cause the amplifier's thermal
cut-out to operate if played at high levels.
The Bridge Mode indicator on the front panel (Fig. 2; No. 4) will
illuminate when the amplifier is in Bridge mode.
NOTES: Do not connect anything to the Right "Fixed In" or Right
"Variable In" sockets when Bridge Mode is selected.
Always turn the C270 and other components in the system off
before connecting or disconnecting anything to the "Fixed In" or
Variable In" sockets.
7. SOFT CLIPPING™
When an amplifier is driven beyond its specified power output, a
hard, distorted sound can be heard on very loud sounds. This is
caused by the amplifier cutting off or 'hard clipping' the peaks of
sound that it was not designed to reproduce. The NAD Soft
Clipping™ circuit gently limits the output of the system to
minimise audible distortion if the amplifier is overdriven.
If your listening involves moderate power levels you may leave the
Soft Clipping™ switch to Off. If you are likely to play at high levels,
that could stretch the amplifier's power capability, then switch Soft
Clipping™ On.
The Soft Clipping™ indicator on the front panel will illuminate
when the amplifier is in Soft Clip mode.
8. 12V TRIGGER AUTO ON-OFF
The C270's 12V trigger input allows it to be switched to On and
Stand-by remotely by an external component.
Set the 12V Trigger switch set to the "ON" position to activate the
12V Trigger input. When the switch is set to the Off position, the
12V trigger input is not active. Refer to section "12V Trigger In"
below for more information.
9. 12V TRIGGER IN
This input allows the C270 to be switched remotely to stand-by
and on or by ancillary equipment such as a preamp, AV processor,
etc. which are also equipped with a 12V trigger output.
For switching Stand-by/Power On of the C270 by an external
component, connect the12V-trigger input of the C270 to the
remote component's DC output jack. The plug required is a
standard 3.5mm Mini-Jack plug ("mono"): The tip is the live or
+ connection, the shaft of the input jack is the 12V-trigger - or
ground connection.
NOTES: The C270's 12V Trigger will work within a range of 6 to
15 V DC level and typically draws less than 10mA of current.
Check the specifications of the Trigger output terminal on the
remote component to ensure it is compatible with the C270's 12V-
trigger input. NAD components equipped with 12V output triggers
are fully compatible with the C270's 12V input trigger.
Before making any connections to any 12V trigger input or output,
make sure all components are disconnected from the AC mains.
Failure to observe the above may result in damage to the C270 or
any ancillary components attached to it. If in doubt over the
connections, installation and operation of the 12V trigger output
consult your NAD dealer.
10. AC LINE CORD
Plug the AC power cord into a live AC wall socket. Make sure all
connections have been made before connecting to mains.
GB
5