NAIM POWERAMPS Manual - page 10
9
9
nap 140, 150, 180, 250 power amplifiers
connections
The negative input and output connections are all common. The mains earth (ground) should always
be connected regardless of what other equipment is used in conjunction with Naim power amplifiers.
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 will normally be in the turntable or cd player.
protection
If the case of a nap 140, 150, 180 or 250 reaches 70°C due to prolonged running at high dissipation,
the mains supply will be interrupted and the indicator light will go off until the amplifier has cooled
down. This may take up to thirty minutes.
The regulated power suppplies in the nap 250 will shut down if more than 17 amps is drawn for more
than 10 microseconds but the indicator light will not go off. To reset, turn the amplifier off for one
minute.
loudspeaker cable
For the best results Naim Audio’s own speaker cable should be used to connect a loudspeaker to the
output of the power amplifiers. Special Naim Audio loudspeaker connectors are supplied to make the
connection to the power amplifier(s). IT IS ESSENTIAL THAT THESE ARE USED, IN ORDER TO
COMPLY WITH CURRENT SAFETY REGULATIONS.
DO NOT, FOR ANY REASON, USE SO CALLED HIGH DEFINITION WIRE OR ANY OTHER SPECIAL
CABLE BETWEEN POWER AMPLIFIER AND LOUDSPEAKER AS DAMAGE MAY RESULT.