A.c. Power Connection - Audio Research Reference 750 SE Manual

A.C. Power Connection

It is important that the Reference 750 SE
be connected via its supplied 20 amp IEC
12-gauge power cord to a secure, dedicated
A.C. power receptacle. Never connect to
convenience power receptacles on other
equipment. Only use the power switch on
the front of the Reference 750 SE for On/Off
control of the amplifier.
The AC power source for the Reference 750
SE amplifier should be capable of supplying
20 amperes for 100 or 120 volt units, or 10
amperes for 220 or 240 volt units.
For the very best performance on 100 or 120
volt circuits, the Reference 750 SE should
be connected to its own AC power circuit
branch, protected by a 20-30 amp breaker.
The preamplifier and other audio equipment
should be connected to a different power
circuit and breaker. If the power receptacle
is more than 25 feet from the building's
power entrance and breaker box, circuit
wiring capable of 30 amperes should be
installed to minimize voltage drop using a
20-amp breaker.
Connections
The Reference 750 SE should be turned
on after the other components of your
system. If the Reference 750 SE is turned on
before other components, the amplifier will
amplify any extraneous turn-on noises those
components might generate, which could
potentially damage the loudspeakers. Good
operating practice dictates that the amplifier
should be turned on last, and turned off first
in an audio system.
The Reference 750 SE uses a grounding system
that does not require a ground-lifter adapter
plug on the A.C. power cord to minimize hum.
The power cord supplied with the Reference
750 SE has a standard grounding plug to
provide maximum safety when properly
connected to a grounded wall receptacle.
If there is any question regarding proper
grounding procedures in your installation,
seek help from a qualified technician. Caution
should be taken before using custom after-
market power cords: they must be at least
12-gauge and have a standard grounding plug
properly installed. These power cords are
to be used with caution, at the sole risk of
the owner.
If electronic crossovers or other AC powered
equipment is used with the Reference
750 SE it may be necessary to use 'ground
lifter' adapters on the power plugs of
that equipment to minimize system hum.
Generally, the lowest hum is achieved when
the only direct connection between audio
common 'ground' and true earth ground
occurs in the preamplifier, through its
grounded power cord. Other equipment in the
system should have some form of isolation
to prevent ground loops and associated hum.
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