e33
NAP 500 Power Amplifier
31.1 General Connections notes
The negative input and output connections for each
channel are 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.
note:
Each channel of the NAP 500 is a “bridged”
amplifier, so none of the speaker outlet sockets (+ or -)
is at earth potential. Avoid connecting mains powered
equipment such as electrostatic speakers, sub-woofers
and headphone energisers that do not have a floating
earth. No plug which is connected directly or indirectly to
earth potential should be attached to any speaker outlet
(+ or -).
31.2 Protection notes
In the NAP 500 the fan speed is increased in response to
an increase in amplifier dissipation. If the amplifier reaches
70°C due to prolonged running at high level or to airflow
being blocked, the output will be interrupted and the fan
will run at full speed until it has cooled down. This may
take a few minutes.
It is not necessary to switch the amplifier off, but it may
be advisable to mute the preamplifier or turn the volume
down to avoid surprises when it comes back on.
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.
31 Installation and operation
The naP 500 and naP 500Ps should be installed on a dedicated equipment stand
intended for the purpose and should be in their 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 500. The naP 500 power button is located on the front
panel of the naP 500Ps Power supply.
Care should be taken when siting the naP 500 to ensure that the top and bottom
ventilation grids are not blocked.
The naP 500 and naP 500Ps are very heavy and care should be taken when lifting or
moving them. make sure that the surface they are to be placed on can support the full
weight.
31.3 Loudspeaker Cable and Connectors
Only Naim Audio speaker cable should be used to
connect a loudspeaker to the output of the NAP 500.
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.
