Installation; Overview; Placing The Unit; Room Acoustics - Arcam P777 Handbook

installation

overview

The P777 Multichannel Power Amplifier is built
to Arcam's traditional high quality design and
manufacturing standards. It is an extremely high-
performance multichannel power amplifier obviously
well suited to multichannel home cinema amplification,
although it also provides superb quality stereo
performance with two-channel sources. The P777 is an
ideal partner for the FMJ AV888 Pre-amp Processor.
Each power amplifier module is identical, and is
electrically isolated from the other modules by opto-
isolated circuitry which ensures that each amplifier
module has its own isolated supply. This allows the
amplifier to give excellent channel separation and very
low distortion.
The P777 also has input and output phono sockets
for the signal being fed to each channel, to allow the
signal to be passed on to additional power amplifiers
to drive loudspeakers in other rooms or to bi-amplify
any of the speakers. If the P777 is being used to drive
a five-channel surround sound system, then the spare
two modules (SBL and SBR) can be used in conjunction
with the main (L and R) modules to bi-amplify suitable
front left and right speakers.
The customised installation of the P777 to a listening
room is an important process which requires care at
every stage. For this reason, the installation information
is very comprehensive and should be followed carefully.
This manual has been written with the assumption that
the installer is familiar with the installation of high-end
audio/video systems.

Placing the unit

Place the P777 on a level, firm surface, avoiding
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direct sunlight and sources of heat or damp.
The P777 is a powerful amplifier and a source of
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considerable heat output when driven hard. Take
this into consideration when placing the unit.
Do not place the unit in an enclosed space such as
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a bookcase or closed cabinet unless there is very
good provision for ventilation.
Do not place any other component or item on top
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of the P777 as this may obstruct airflow around
the unit, causing the P777 to run hot.
Do not place your record deck on top of this
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unit. Record decks are very sensitive to the noise
generated by mains power supplies which will be
heard as a background 'hum' if the record deck is
too close.

Room acoustics

The shape of your room and how it's furnished will affect
the sound you hear. For instance, too many bare surfaces
can cause reflections that may add harshness to the
sound. Adding carpeting and drapes can help.
If you have a choice of rooms, avoid ones that are
perfectly square or have one dimension exactly twice
another. These rooms can aggravate resonances that
colour the sound.

12V Trigger input

If your pre-amp provides a 12V Trigger output, it can
be connected to the socket using a mono
12V TRIGGER IN
3.5mm jack. This enables the P777 to be turned on
remotely from the pre-amp.
tip: 12V trigger signal
sleeve: ground
Note that the trigger input is only active when the
central power button on the front panel is depressed.
In normal use there is no need to make any connections
to this input.
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Power

The P777 is supplied with a moulded mains plug already
fitted to the lead. Up to 3kW is drawn at maximum
levels, so a heavy duty IEC mains cable is supplied.
Check that the plug supplied fits your supply – if your
mains supply voltage or mains plug is different, or you
need a new mains lead, please contact your Arcam
dealer.
Push the IEC plug end of the power cable into the socket
on the back of the P777, making sure that it is pushed in
firmly. Plug the other end of the cable into your mains
socket and, if necessary, switch the socket on.

connecting to a pre-amplifier

Two different connection types are provided for
receiving signals from your pre-amplifier: phono
sockets and XLR connectors. The connection type to use
depends on the set-up that you have.
If the cables to be used to connect your pre-
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amplifier to the P777 are less than 3m long, we
recommend connecting your pre-amplifier to the
phono (RCA) sockets of your P777. To
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use the phono connections, make sure that all the
channel input switches are not depressed.
If the cables to be used to connect your pre-
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amplifier to the P777 are 3m or longer and your
pre-amplifier has balanced XLR outputs, we
recommend using these instead of the phono
(RCA) connections. Performance will also be
improved in electrically-noisy environments
by using these connections. To use the XLR
connections, make sure that the
INPuT sElEcT
switches are depressed for each channel.
Female XLR Male XLR
2 1 1 2
3
3
Pin Function
1 Chassis ground (cable shield)
2 'Hot' (normal polarity)
3 'Cold' (inverted polarity)