Audio Research FOUNDATION Series, Руководство пользователя

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other components of your system. If the VT80
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 VT80 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 VT80 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 VT80 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.
Remote Turn-on
The VT80 SE has a built-in 12VDC remote
turn-on/off circuit for operation by a master
control system in a home theater or large
audio system. Use a 3.5mm (.140”) diameter
mini plug to connect to the +12V TRIGGER IN
jack on the rear of the VT80 SE.
The +12V TRIGGER IN jack should be
connected to the +12VDC output of the
master control system, using a continuous
+12VDC signal at 12mA per VT80 SE for the
duration of amplifier on-time. Do not use a
momentary or data pulse control signal.
The +12VDC remote jacks have polarity
protection, so they will not operate if a
-12VDC signal is accidentally connected, or if
the control wires are reversed.
Connections Connections
Connect the VT80 SE input to the preamplifier
or electronic crossover, using only the
highest grade of audio interconnect cables.
To avoid sonic degradation use the shortest
practical length of cables.
Note:
The VT80 SE will not be
damaged by improper impedance match to
the speakers, but maximum power delivered
into the speakers may be affected.
A.C. Power Connection
It is important that the VT80 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 VT80
SE for On/Off control of the amplifier, or the
12V start-up trigger for remote installations.
The AC power source for the VT80 SE
amplifier should be capable of supplying
10 amperes for 100 or 120 volt units, or 5
amperes for 220 or 240 volt units.
For the very best performance on 100 or
120 volt circuits, the VT80 SE should be
connected to its own AC power circuit
branch, protected by a 15 amp breaker. The
preamplifier and other audio equipment
should be connected to a different power
circuit and breaker.
The VT80 SE should be turned on after the
RS-232 Control
The VT80 SE has an RS-232 connector on
the back panel, in the event the amplifier is
incorporated into an automated or two-way
remote communication system. Please see
your dealer or contact customer service at
Audio Research to acquire the specific codes
relative to the RS-232 control.