NAIM SNAXO 242 - V1 User manual

WORLD CLASS HI FI
OWNERS MANUAL
Active Crossovers: SNAXO 362, SNAXO 242
ISSUE 1

1
2 Cables and Connections
Please do not modify the standard interconnect cables
supplied with your Naim equipment. This is important for
safety as well as performance. One end of each cable is
marked with a band to establish its correct orientation.
The band always marks the end that connects to the
signal source.
Loudspeaker leads are also very important. Naim
loudspeaker cable is correct for your system and your
dealer will make up leads to suit your equipment
installation. The leads should each be at least 3.5 metres
long and of equal length. The recommended maximum is
20 metres. Loudspeaker leads are, like interconnect leads,
directional, and should be connected so that the printed
arrow points towards the speakers. Using alternative
loudspeaker cable will degrade performance, and may even
damage your amplifier. An exception to these loudspeaker
cable constraints is the NAP 6-50 multi-room power
amplifier. The NAP 6-50 is designed to be tolerant of both
a wide variety of cable types, and cable runs well in excess
of 20m. The loudspeaker connectors supplied with all Naim
amplifiers and loudspeakers have been specifically
designed to make a robust mechanical connection. It is
essential that these are used in order to comply with
current European safety regulations.
All the plugs and sockets supplied with your Naim
equipment have been chosen because they make the best
possible connection for their purpose. A poor contact will
degrade the signal substantially and plugs and sockets
should look clean and free from corrosion. The easiest way
to clean them is to switch off the equipment, pull the plugs
out of their sockets, and push them back in again. Special
contact cleaners and contact enhancers should not be
used as they tend to deposit a film which is very difficult to
remove and may degrade the sound.
1 Equipment Installation
Normally your Naim equipment will have been installed by the dealer who sold it to you
even if you live outside their immediate vicinity. Your dealer is responsible for making
sure that the system sounds exactly as it should and information given here is not
intended to reduce this responsibility in any way.
Introduction
Naim Audio products are always conceived with performance as the
top priority and careful installation will help ensure that their full
potential is achieved. This manual begins with statutory safety
warnings and general installation tips for all Naim Audio products.
Product specific information begins in Section 6.
3 Getting Started
3.1 switching on and off
Source components and power supplies for cd players,
tuners, preamplifiers and crossovers should be switched
on before switching on the power amplifier(s). Always
switch the amplifier(s) off and wait about a minute for
the power supply capacitors to discharge before
connecting or disconnecting any leads. Always use the
power switch on the product rather than a mains outlet
switch.
3.2 running in
Your Naim equipment will take a considerable time to run
in before it performs at its best. The duration varies, but
under some conditions you will find that the sound
continues to improve for as much as five weeks. Better and
more consistent performance will be achieved if the system
is left switched on for long periods. It is worth
remembering however that all electronic equipment can be
damaged by lightning. Please read the warnings section.
CONTENTS
Page Section
1 1 Equipment Installation
1 2 Cables and Connections
1 3 Getting Started
3.1 switching on and off
3.2 running in
23.3 mains supply
3.4 siting the equipment
3.5 if you have a problem
2 4 Warnings
3 5 Connection
5.1 mains lead
5.2 mains plugs
5.3 fuse carrier
5.4 plug fuses
4 6 SNAXO Installation and
Operation
4 7 SNAXO Rear Panel
Diagrams
5 8 SNAXO Power Supply
Connection Diagrams
6 9 SNAXO to Amplifier
Connection Diagrams
9 Standards Declaration

2
3.3 mains supply
Where fused plugs are used 13 amp fuses should be fitted.
Fuses of a lower rating will fail after a period of use.
A hi-fi system usually shares a mains circuit with other
household equipment some of which can cause distortion
of the mains waveform. In some Naim equipment such
distortion can lead to a mechanical hum from the
transformers. The hum is not transmitted through the
speakers and has no effect on the performance of the
system but is purely local to the transformer itself. A
separate fused mains circuit (like that reserved for electric
cookers) may reduce transformer hum. Such a circuit
(ideally with a 30 or 45 Amp rating) will also have a lower
impedance, supply cleaner power, and consequently
improve system performance.
Do not wire voltage dependent resistors or noise
suppressors into mains plugs. They degrade the mains
supply and the sound.
3.4 siting the equipment
Power supplies and amplifiers should be located a
reasonable distance away from other equipment. This
separation will stop transformer radiation causing hum
audible from the loudspeakers. The maximum separation
distance for connected equipment is that allowed by the
standard interconnect lead.
Some Naim equipment is extremely heavy. Ensure that your
equipment rack or table can easily support the weight and
is stable.
3.5 if you have a problem
Legal consumer protection varies from country to country.
In most territories a dealer must be prepared to take back
any Naim equipment he has sold you if he cannot make it
work to your satisfaction in your own home. A problem may
be due to a fault in any part of the system or its
installation so it is essential to make full use of your local
dealer’s diagnostic skills on site. Please contact your local
distributor, or Naim at the address in the back of this
manual, if any difficulties cannot be resolved. Some Naim
equipment is made in special versions for different
territories and this makes it impracticable to arrange
international guarantees. Please establish the guarantee
arrangements with your own dealer at the time of sale. We
are always available to offer help and advice.
It is essential that repairs and updates are only carried out
by an authorised Naim dealer, or at the factory by Naim
itself. Many components are made, tested or matched
specially for Naim and appropriate replacements are often
unobtainable from non-specialist sources.
4 Warnings
Naim equipment is designed to offer the finest sound
quality that can be achieved avoiding compromise
wherever possible. This can lead to circumstances that
may be unfamiliar. The material that follows contains
advice specifically related to Naim equipment as well as
more general warnings about the use of domestic audio
products. Please read it carefully.
The transformers in Naim power amplifiers and power
supplies may sometimes make a mechanical noise caused
by distortion of the mains waveform. Naim transformers are
large in size and have heavy gauge secondary windings
making them relatively sensitive to such distortion. A
separate mains circuit for your hi-fi system may reduce the
effect while also giving an overall improvement in sound
quality. It may be necessary however to take account of
mechanical transformer noise when siting your equipment.
IMPORTANT
In order to comply with
current European safety
regulations it is essential
that the Naim loudspeaker
connectors supplied with
amplifiers and loudspeakers
are used.
Do not under any
circumstances allow anyone
to modify your Naim
equipment without first
checking with the factory,
your dealer, or your
distributor. Unauthorised
modifications will invalidate
your guarantee.
For your own safety do not
under any circumstances
open Naim equipment
without first disconnecting
the mains.
The following label is
attached to all mains
powered equipment:
WARNING
THIS APPARATUS
MUST BE EARTHED
Introduction

3
In some circumstances, depending on where you live and
the earthing arrangements in your home, you may
experience radio frequency interference. Controls on
broadcasting in some territories allow very high levels of
radio frequency radiation and both the choice and exact
siting of equipment may be critical. If there is a known
problem in your locality it is advisable to arrange for a
home demonstration before purchase to find out if Naim
equipment is likely to be affected. Susceptibility to radio
frequency interference is related to the wide internal
bandwidth necessary for high sound quality. Systems
incorporating moving coil phono preamplifiers and active
crossovers are more likely to suffer. A radio frequency filter
kit is available for some Naim equipment but sound quality
will be progressively compromised as more elements of the
kit are fitted. In situations of extreme radio interference
Naim equipment may be unsuitable.
Your Naim hi-fi system can be damaged by lightning. Power
amplifiers are particularly at risk and should be turned off
when there is risk of lightning strike. For complete
protection all mains plugs and any aerial cables should be
disconnected when not in use.
Equipment must not be exposed to dripping or splashing
and no objects filled with liquid, such as vases, should be
placed on the equipment.
Use of non-standard speaker cables or interconnects may
invalidate your guarantee.
5 Connection
5.1 mains lead
As the colours of the wires in the mains lead of this
apparatus may not correspond with the coloured markings
identifying the terminals in your plug proceed as follows:
The wire which is coloured GREEN-AND-YELLOW must be
connected to the terminal in the plug which is marked by
the letter E or by the safety earth symbol or coloured green
or green-and-yellow.
The wire which is coloured BLUE must be connected to the
terminal in the plug which is marked with the letter N or
coloured black.
The wire which is coloured BROWN must be connected to
the terminal in the plug which is marked with the letter L or
coloured red.
5.2 non-rewireable mains plugs
If a non-rewireable plug is cut from a mains lead (for
whatever purpose) the plug MUST be disposed of in a way
to render it totally useless. Considerable shock hazard
exists if the cut-off plug is inserted into a mains outlet.
5.3 fuse carrier
Should the plug fuse carrier be damaged or lost, the
correct replacement must be obtained from your dealer, or
from Naim Audio direct. Do not use the plug until the fuse
carrier is replaced.
5.4 plug fuses
Replace only with ASTA or BS 1362 approved fuses.
NOTE
This equipment has been tested and found to comply with the relevant EMC and Safety
Standards, and, where applicable, also complies with the limits for a class B digital device,
pursuant to Part 15 of the FCC Rules.
These limits are designed to provide reasonable protection against harmful interference in
a residential installation. This equipment generates, uses and can radiate radio frequency
and, if not installed and used in accordance with the instructions, may cause harmful
interference to radio communications. However, there is no guarantee that interference will
not occur in a particular installation. If this equipment does cause harmful interference to
radio or television reception, which can be determined by turning off and on, the user is
encouraged to try to correct the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and the receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver
is connected.
• Consult your Naim dealer or an experienced radio/TV technician for help.
Introduction

Active Crossover Rear Panels
4
6.1 level adjustment
Level adjustment for each crossover output section is available
within the SNAXO 362 and 242. As delivered, the level
adjustment is set nominally flat. Contact your dealer for further
information and advice on level adjustment.
Active Crossovers
6 Installation and Operation
The SNAXO 362 and 242 Active Crossovers can only be operated using an appropriate
Naim power supply. Connection of power supplies and of some common amplifier
options is illustrated in the diagrams starting on Page 5. Contact your dealer or Naim
Audio directly for advice on alternative amplifier options. The crossovers will switch on
automatically after a short delay when connected to a live power supply.
SNAXO 362 and 242 should be installed on a dedicated equipment stand intended for
the purpose.
7.1 SNAXO 362
ch1
nc
-ve
ch2
Output Sockets
+ve
ch2
-ve
+ve
Input/PSU Socket
B
A
LF HF
Input/Power Supply Socket
Output Sockets Supercap Power
Supply only
ch1
Note
A and B output sockets
are identical.
ch1
nc
-ve
ch2
Output Sockets
+ve
ch2
-ve
+ve
Input/PSU Socket
B
A
LF MF HF
Input/Power Supply Socket
Output Sockets Supercap Power
Supply only
ch1
Note
A and B output sockets
are identical.
7.2 SNAXO 242

5
SNAXO Power Supply Connection
8.1 SNAXO 362 connected to Supercap Power Supply
8.2 SNAXO 242 connected to Hi-Cap Power Supply
mains input from preamplifier power supply
Supercap
SNAXO
SNAXO
mains
input
Hi-cap
from preamplifier
power supply
cable
direction
marker
4 to 4 pin DIN
240° 5 to 5 pin DIN
Burndy
Interconnect Cables
Link Plug
in place

6
SNAXO Connection
9.1 SNAXO 362 connected to three NAP 300 Power Amplifiers
left
speaker HF
-+
right
speaker HF
-+
left
speaker MF
-+
right
speaker MF
-+
left
speaker LF
-+
right
speaker LF
-+
SNAXO
NAP 300
NAP 300
NAP 300
cable
direction
marker
4 pin DIN to XLR (Left)
4 pin DIN to XLR (Right)
Interconnect Cables
Notes
• Left and right handed DIN to XLR cables are required.
• Power amplifier power supplies are not shown.
• Connection to three NAP 500s follows the same
principle.

mains in left
speaker LF
-+
right
speaker LF
-+
mains in left
speaker MF
-+
right
speaker MF
-+
mains in left
speaker HF
-+
right
speaker HF
-+
7
SNAXO Connection
9.2 SNAXO 362 connected to three NAP 250 Power Amplifiers
NAP 250
NAP 250
NAP 250
SNAXO
cable
direction
marker 4 pin DIN to XLR
Interconnect Cables

8
SNAXO Connection
mains in left
speaker LF
-+
right
speaker LF
-+
mains in left
speaker HF
-+
right
speaker HF
-+
9.3 SNAXO 242 connected to two NAP 250 Power Amplifiers
NAP 250
NAP 250
SNAXO
cable
direction
marker 4 pin DIN to XLR
Interconnect Cables
Note
• Connection to two NAP 200s or NAP 150s follows the
same principle but with 4 pin DIN to 4 pin DIN cables.

9
Declaration of conformity to appropriate standards
Manufacturer
Naim Audio Limited, Southampton Road, Salisbury, England, SP1 2LN
Products
SNAXO 362, SNAXO 242
Safety
HD 195-S6
EN 60 065
EMC
Emissions Tested to: EN 55013 - Sound and television broadcast receivers and associated equipment
Immunity Tested to: EN55020 - Electromagnetic immunity of broadcast receivers and associated equipment
In accordance with: CISPR 16-1 - Radio disturbance and immunity measuring apparatus
CISPR 16-2 Methods of measurement of disturbances and immunity
IEC 801-2 8kV (air gap) 4kV (contact) (performance criterion B)
IEC 801-3 3V/m 20dB (performance criterion A)
IEC 801-4 1kV (AC lines) 0.5kV (signal lines) (performance criterion B)

Naim Audio Limited, Southampton Road, Salisbury, England SP1 2LN
Telephone: [phone] Fax: [phone] www.naim-audio.com
Part No. OWMXO 12-001-0040
Drawing No. NA503001-400