Naim Audio NAC-N 172 XS - Manual (Page 42)

E40
46.1 General Connections Notes
The negative input and output connections are all
common. The mains earth should always be connected
regardless of what other equipment is used. This only
grounds the case and the electrostatic screen within the
transformer, and is not connected to the signal negative. In
order to avoid hum loops, the signal negative of the whole
system should be connected to the mains earth (ground) in
one place.
46.2 Protection Notes
If the amplifier’s external case reaches 70°C due to
prolonged running at high power, the mains supply will be
interrupted and the illuminated logo will switch off until
the amplifier has cooled down. This may take up to thirty
minutes.
46 Installation and Operation
The NAP 155 XS should be installed on a dedicated equipment stand intended for the
purpose and should be 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 NAP 155 XS. The NAP 155 XS power switch is located on the rear panel.
The NAP 155 XS can provide power for an appropriate Naim Audio preamplifier. The
power supply output is carried on the DIN input socket.
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.
46.3 Loudspeaker Cable and Connectors
Only Naim Audio speaker cable should be used to connect
a loudspeaker to the output of the NAP 155 XS. 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 both channels.
48 NAP 155 XS Specification
Power Output: 60 Watts per channel, 8Ω
Quiescent Consumption: 10VA
Voltage Gain: +29dB
Input Impedance: 18kΩ
Frequency Response: -3dB @ 3Hz and 50kHz
Power Supply Output: 24V, 0.25A
Dimensions (H x W x D): 70 x 432 x 301mm
Weight 7.5kg
Mains Supply: 100V, 115V or 230V, 50/60Hz
mains input
and fuse
signal input
ch1(L) & ch2(R) and
preamp power
supply
ch2 ch1
24V
0.25A
Input/Preamp
Power Socket
-ve
power
switch
NAP 155 XS Power Amplifier
47 NAP 155 XS Connections
47.1 NAP 155 XS Rear
left
speaker
right
speaker
Note: The NAP 155 XS features various technologies to
reduce microphonic effects. Some movement of the board
and sockets when connecting and disconnecting cables is
normal.