manual

E41
49.1 General Connections Notes
The mains earth grounds only the case and the
electrostatic screen within the transformer and is not
connected to the signal negative. The mains earth must
always be connected to “ground” regardless of any other
equipment used. In order to avoid hum-loops the signal
negative of the whole system should be connected to the
mains earth in one place.
49.2 Protection Notes
Once installed the NAP V175 is intended to remain
permanently powered up via its rear panel switch. If the
internal heatsink reaches 70°C due to prolonged running
at very high dissipation the mains supply will be interrupted
and the illuminated logo will go off until the amplifier has
cooled down. This may take up to thirty minutes.
49 Installation and Operation
The NAPV 175 is a three channel power amplifier intended for use in audio-visual systems.
The three channels provide power to drive a centre channel speaker and a pair of
either main front or surround channel speakers. Audio line level input is via two 4-pin DIN
sockets - one for the centre channel and one for the main or surround pair.
The NAPV 175 should be installed on an equipment rack intended for the purpose and
in its final location before connecting cables or switching on. Switch on the source and
preamplifier components, with the volume turned down, before switching on the NAPV
175. The power switch is located on the rear panel.
The NAPV 175 is heavy and care should be taken when lifting or moving it. Make sure that
the surface it is to be placed on can support the full weight.
OPERATION OF THE AMPLIFIER’S THERMAL PROTECTION
SUGGESTS PROLONGED USE AT TOO HIGH A VOLUME LEVEL.
YOUR LOUDSPEAKERS MAY BE AT RISK IF THIS IS THE CASE.
THE VOLUME SHOULD BE REDUCED.
49.3 Loudspeaker Cable and Connectors
Only Naim Audio speaker cable should be used to
connect a loudspeaker to the output of the NAPV 175.
Custom Naim Audio loudspeaker connectors are supplied
to make the connection and in order to comply with
current European safety regulations these should always
be used.
DAMAGE TO THE AMPLIFIER MAY RESULT IF “HIGH
DEFINITION” CABLE OR ANY OTHER SPECIAL CABLE IS USED
TO CONNECT THE LOUDSPEAKERS.
Ensure when connecting speakers that they are “in
phase”. That is, the positive and negative connection
orientation at both the speaker and amplifier ends of the
cable is the same for all channels.
51 NAPV 175 Specification
Power Output: 50 Watts per channel, 8Ω
Channels: Three
Quiescent Consumption:
10VA
Voltage Gain:
+29dB
Input Impedance:
18kΩ
Frequency Response: -3dB @ 3Hz and 50kHz
Dimensions (H x W x D): 70 x 432 x 301mm
Weight 7.9kg
Mains Supply: 100-120V or 220-240V, 50/60Hz
mains
input and
fuse
signal input
ch1(L) &
ch2(R)
power
switch
signal
input
centre
nc
signal
nc
Input - Centre
-ve
ch2
ch1
nc
Input -
Ch1 & Ch2
-ve
NAPV 175 Power Amplifier
left
speaker
right
speaker
centre
speaker
50 NAPV 175 Connections
50.1 NAPV 175 Rear