Power Drive - NAD C375BEE Owner's Manual

8 PRE OUT 1: The PRE OUT 1 sockets can be used to drive an additional
power ampli er. Use a twin RCA-to-RCA lead to connect to the left and
right "Audio Input" of the Power ampli er or processor to the PRE OUT 1
sockets.
Always turn the C 375BEE and associated external power ampli ers OFF
before connecting or disconnecting anything to the PRE OUT 1 sockets.
The PRE OUT 1 output signal will be a ected by the C 375BEE's volume
and tone control settings.
9 MAIN IN: Connections to an external pre-ampli er or processor, such
as a surround-sound decoder. In normal use, this should be connected
to PRE OUT 2 sockets with the links supplied. To connect your NAD
C 375BEE to external processor or pre-ampli er, remove rst these links.
Use a twin RCA-to-RCA lead to connect the left and right "Audio Output"
of the pre-amp or processor to the Main In sockets.
Always turn the C 375BEE and associated external power ampli ers OFF
before connecting or disconnecting anything to the MAIN IN sockets.
10 PRE OUT 2: Connections to an external power ampli er or processor, such
as a surround-sound decoder. In normal use, this should be connected to
the Main In sockets with the links supplied. To connect your NAD C 375BEE
to external processor or ampli er sections, remove rst these links. Use a
twin RCA-to-RCA lead to connect the left and right "Audio Input" of a power
ampli er or processor to the PRE OUT 2 sockets.
Always turn the C 375BEE and associated external power ampli ers OFF
before connecting or disconnecting anything to the PRE OUT 2 sockets.
The PRE OUT 2 output signal will be a ected by the C 375BEE's volume
and tone control settings.
11 VOLUME PRE OUT 2: The VOLUME PRE-OUT 2 control allows for
adjustment of the output level of the PRE OUT 2 sockets. Turn clockwise
to increase the PRE OUT 2 volume setting; counter clockwise to lower
it. When set to the maximum position, the output level will be identical
to that of the PRE OUT 1 sockets. Refer also to the item below about
"Bi-Amping".
BI-AMPING
Some loudspeakers have separate connection terminals for the LF (Low
Frequency) and HF (High Frequency) sections of the speaker. This facility
allows to "Bi-Amp" these speakers, where a separate power ampli er
is used for the LF and HF section, which may improve overall sound
quality.
The C 375BEE provides two sets of preampli er outputs (PRE OUT 1 and
PRE OUT 2) to facilitate the connections for Bi-Amping. Moreover, the level
from PRE OUT 2 can be reduced in relation to PRE OUT 1 to accommodate
power ampli ers with di erent gain (ampli cation factor).
To set up the C 375BEE with power ampli ers rst decide which power
ampli er has the highest gain. This is easily done by comparing the
loudness level of the power ampli ers in an identical system (keep the
volume control at the same level; use the same source and speakers).The
ampli er that plays louder has the highest gain (note that this does not
need to be the more powerful ampli er of the two). Connect the ampli er
with highest gain to the PRE OUT 2 sockets; the other power ampli er to
the PRE OUT 1 sockets. From the maximum level position, use the VOLUME
PRE OUT 2 control to reduce the output level of PRE OUT 2 so that the
volume level of both power ampli ers is exactly matched.
IDENTIFICATION OF CONTROLS
12 BRIDGE MODE: The C 375BEE ampli er can be con gured to be
MONO (Bridge Mode), more than doubling its output power. This way,
the C 375BEE can be used as part of a high power stereo or home-
theatre system, by connecting additional power ampli ers.
In BRIDGED MODE (switch at ON setting), the C 375BEE will produce
approximately 330W into an 8 ohm loudspeaker. In this mode, the
ampli er 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 ampli er's thermal
cut-out to operate if played at high levels.
Set the BRIDGE MODE switch to the "ON" position and connect the
speaker to the terminals marked "L +" and "R+" ensuring that the "L+"
is connected to the "+" terminal of your loudspeaker and the "R+" is
connected to the loudspeaker's " - " terminal. Connect the source to
the Left INPUT sockets.
The BRIDGE MODE indicator on the front panel will illuminate when the
C 375BEE is in Bridge mode. Return normal speaker connections (Refer
also to the item below about "SPEAKERS A,B"). and keep BRIDGE MODE
switch to "OFF" position for normal stereo listening.
NOTE
Do not connect anything to the Right Input socket when Bridge Mode is
selected.
13 SOFT CLIPPING™: Enables NAD's proprietary Soft Clipping circuitry
on all channels. At [ON] position, Soft Clipping gently limits the output
of the C 375BEE to minimize audible distortion should the ampli er be
over-driven. Soft Clipping may simply be left ON at all times to reduce
the likelihood of audible distortion from excessive volume settings.
However, for critical listening and to preserve optimum dynamics, you
may wish to defeat it by setting this switch to "OFF" position.
The SOFT CLIPPING indicator on the front panel will illuminate when
the C 375BEE is in Soft Clipping mode. See also below the item about
"POWERDRIVE".
POWERDRIVE
The C 375BEE uses NAD's proprietary PowerDrive™ ampli er technology
for all channels to preserve accurate, linear reproduction regardless
of the loudspeaker. This uniquely e cient power-supply topology
provides the real-world bene ts of high dynamic power that remains
uncompromised by low-impedance speakers.
By adding a second high-voltage rail to our well regulated high-current
power supply, we get an "overdrive" that can nearly double the continuous
power on a short term dynamic power basis. PowerDrive o ers greater
ampli er stability and low impedance drive capability, resulting in less
distortion when driving real speakers with real program material.
REAR PANEL
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