8
10.1 connection 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. This
should be the primary signal source.
10.2 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.
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.
10.3 loudspeaker cable and connectors
Only Naim Audio speaker cable should be used to connect
a loudspeaker to the output of the NAP 250. Custom Naim
Audio loudspeaker connectors are supplied to make the
connection.
IN ORDER TO COMPLY WITH CURRENT
EUROPEAN SAFETY REGULATIONS IT IS ESSENTIAL THAT
THESE ARE USED.
DAMAGE TO THE AMPLIFIER MAY RESULT IF “HIGH
DEFINITION” CABLE OR ANY OTHER SPECIAL CABLE IS
USED TO CONNECT THE LOUDSPEAKERS.
NAP 250
10 Installation and Operation
The NAP 250 should be installed in its final operating location before connecting cables
or switching on. Switch on the source and preamplifier components, with the volume
turned down, before switching on the NAP 250. The NAP 250 power button is located on
the front panel.
The NAP 250 is very 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.
