Rear panel connections
1. Power on/off
Switches the 851N on and off.
2. Mains voltage selector switch (CU version only)
Switches the mains voltage between 100V and 115V.
Note:
For use by Cambridge Audio service personnel only!
3. Power socket
Once all other connections are made, connect the supplied power cable to the
851N power socket and to an appropriate mains socket. The 851N is now ready
for use.
4. USB sockets
Wi-Fi Dongle – Should be in the upright position as shown. Allows connection to
802.11b/g or n networks (2.4 GHz will only be used for n networks).
Local Media – Use to connect a USB storage device or another portable device that
is USB HD/flashdisk compatible containing music files. Alternatively an optional
Cambridge Audio BT100 Bluetooth Adaptor can be plugged in here adding wireless
streaming audio capability directly from most phones, tablets and laptops. See
later section for details.
Note: The USB ports are not intended for connection to Apple mobile devices, no
functionality, charging or otherwise is supported.
5. Ethernet
Ethernet port for connecting to a 10/100BASE-T local area network (LAN).
6. Digital inputs
The 851N has four digital inputs in total featuring both S/PDIF co-axial and
TOSLINK optical sockets.
D2/D4 TOSLINK Optical – Use a high quality TOSLINK fibre optic interconnect cable
designed specifically for audio use. This input is suitable for 16-24 bit content up to
192kHz (using high quality TOSLINK optical cable).
Note: Although TOSLINK connections on the 851N work up to 192kHz with high
quality cables, TOSLINK is not usually recommended with sampling rates above
96kHz.
D1/D3 Coaxial – Use a high quality 75 ohm digital RCA Phono interconnect cable.
This input is suitable for 16-24 bit content up to 192kHz.
7. Digital outputs
The 851N digital outputs enable a separate DAC (digital to analogue converter)
or digital recording device to be connected. Refer to the ‘Operating instructions’
section for more information.
Two concurrent digital outputs are available. Note that these outputs pass through
the currently selected audio source unprocessed, i.e. no volume control or up-
sampling is performed on the digital outputs.
Coaxial
– To obtain best results, use a high quality 75 ohm digital RCA interconnect
cable (not one designed for normal audio use).
TOSLINK Optical
– Use a high quality Toslink fibre optic interconnect cable
designed specifically for audio use.
8. USB Audio In
A USB B type socket is fitted to the 851N to enable the playback of audio from a
personal computer running either Microsoft Windows or Apple Mac OS X operating
systems, most Linux distributions are also suitable.
Note: Always use a high quality USB connection cable certified as USB Hi-
Speed. USB cable connections longer than 3m may result in inconsistent audio
performance.
Always turn the Volume to minimum, switch to another input or
turn the 851N off before plugging/unplugging cables to the USB
input or whilst booting up/shutting down your PC/Mac.
Ground lift switch
The Ground Lift Switch enables the USB interface earth to be disconnected from
the 851N chassis earth. Disconnecting (lifting) the earth can be useful if electronic
hum is heard through the speakers. The switch should otherwise be left in the
Ground position.
9. RS232C Interface
The RS232C interface enables external serial control of the 851N in custom
installation applications. A command set is available on the Cambridge Audio
website at www.cambridgeaudio.com. The RS232 interface can also be used by
Cambridge Audio service personnel for software updates.
10. IR (Infra Red) Emitter In
A 3.5mm mini-jack socket that enables modulated IR commands from multi-room
or IR repeater systems to be received by the 851N.
Note:
Commands received by the IR Emitter In socket are not looped out of the
Control Bus. Refer to the ‘Custom Installation’ section for more information.
11. Control Bus
In
– An RCA phono socket that enables un-modulated commands from multi-rooms
systems or other components to be received by the 851N.
Out
– An RCA phono socket that provides control bus output commands for further
downstream units. This can be useful if using the iPhone/Android app to control
the volume on an Azur amplifiers.
12. AES/EBU Balanced
In
– For sources with a balanced (AES/EBU) digital output. This input is suitable for
16-24 bit content up to 192kHz.
Out
– For external devices incorporating a balanced (AES/EBU) digital input.
13. Unbalanced Audio Output
A conventional RCA phono stereo output for connection to the line-level inputs of
an amplifier. Use a high quality stereo RCA phono interconnect cable intended for
analogue audio signals.
14. Balanced Audio Output
The 851N features balanced outputs on two XLR sockets. Balanced outputs
provide slightly better audio performance and can reject cable-borne noise and
interference when used with equipment with balanced inputs.
Note:
XLR connectors should be wired as follows:
Pin 1: Ground
Pin 2: Hot (in-phase)
Pin 3: Cold (phase-inverted)
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