5
2. Installing and Connecting
2.3 Headphone Output
The NAC-N 172 XS and NAC-N 272 are equipped on their
front panels with 3.5mm and 6.3mm stereo headphone
sockets respectively. Insertion of a headphone plug will
mute the preamplifier outputs. Removal of the plug will
restore the outputs.
Note: NAC-N preamplifiers control and store volume
settings separately for headphones and speakers.
2.4 DAB/FM Aerial Connection
The NAC-N preamplifier DAB/FM tuner module requires a
strong, interference-free signal to enable high quality DAB
and FM reproduction. The rear panel DAB/FM Aerial socket
should be connected, via 75 ohm low-loss coaxial cable, to a
suitable aerial. The aerial should be mounted clear of large
obstructions and as high as possible; ideally on a roof.
Note: Your local Naim retailer should be able to offer
advice on a suitable aerial and aerial installer.
2.5 Signal Ground Switch
Your NAC-N preamplifier is fitted on its rear panel with a
Signal Ground switch offering two positions: Chassis and
Floating. Select the Chassis position unless the NAC-N
preamplifier is connected in a hi-fi system incorporating
another earthed source component, or mains “hum” is
audible through the loudspeakers. Contact your retailer,
distributor or Naim for advice if necessary.
Note: “Connected” in the context above means an
analogue audio signal cable that includes an earth
connection. The digital inputs are isolated from the mains
earth regardless of the Signal Ground switch.
Note: All Naim CD players are earthed so the Signal
Ground switch should be set to floating if one is
connected in the system.
No damage will be done if the wrong Signal Ground position
is chosen, however the system sound quality may be
compromised.
Note: NAC-N preamplifier analogue input and output
negative connections for each channel are common.
The mains earth (ground) should always be connected
regardless of what other equipment is used. The mains
earth primarily grounds the case and the electrostatic
screen within the transformer, and is only connected to
the signal negative if the Signal Ground switch is set to
Chassis. In order to avoid hum loops, the signal negative
of the whole system should be connected to the mains
earth in one place only.
2.6 USB Interface
NAC-N preamplifiers are fitted with a front panel USB
interface intended for the connection of USB memory sticks
carrying audio files. The USB interface should not be used
for any other purpose.
Note: Most UMS (Universal Mass Storage) USB memory
sticks are compatible with the NAC-N preamplifier USB
audio interfaces. Other UMS devices might include
portable digital music players, smart-phones, tablet
computers and memory card readers. Non-UMS USB
devices, such as older MP3 players, may be connected
to a NAC-N preamplifier analogue audio input from their
headphone sockets. See Section 7 for more information.
2.7 Network Connections
2.7.1 Wired Network Connection
NAC-N preamplifiers are fitted on their rear panels with a
standard RJ45 Ethernet socket. This socket enables them to
join home networks via a network router to access internet
radio streams, to play audio files stored on UPnP™ servers,
to play Spotify
®
Connect and TIDAL streams, and to play
from or broadcast to other Naim streamers on the same
network.
Note: Ethernet-over-mains hardware may be used and
provides a simple and convenient method of wired home
network connection. However, depending on mains wiring
factors specific to each home environment, the presence
of network data on the mains supply may compromise
overall system sound quality. If any sound quality
compromise is found to be unacceptable, dedicated
network cabling should be installed as the preferred
option, or alternatively wireless networking can be
employed.
2.7.2 Wireless Network Connection
If your NAC-N preamplifier is to connect wirelessly to the
home network, the supplied Wi-Fi aerial must be fitted to
the rear panel Wi-Fi aerial socket. Wireless configuration
will also be necessary before network connection can be
made. See Section 4.7.1.
Note: The Wi-Fi aerial is the longer one.
Note: An optional high-gain Wi-Fi antenna, the WA5,
is available. The WA5 may improve Wi-Fi connection
reliability in some installations. Contact your Naim retailer
for more information.
