For “bi-wired” loudspeaker systems (i.e. running separate
wires to bass and treble speaker terminals), simply repeat
the above instructions, taking care that all connections
have the same (+) or (-) polarity.
AC POWER CONNECTIONS:
It is essential that the DS450
amplifier be connected to a wall AC power receptacle, or a
similar heavy-duty source. If it is connected to convenience
receptacles on preamplifiers, etc., the full sonic
capabilities of both the amplifier and the preamplifier will
be compromised. The AC power source for the amplifier
should be capable of supplying 15 amperes for 100 or 120
volt units, or 8 amperes for 220 or 240 volt units.
For the very best performance on domestic 100 or 120 volt
circuits, the DS450 should be connected to its own AC
power circuit branch protected by a 15 amp breaker. The
preamplifier and other audio equipment should be connect-
ed to a different power circuit and breaker. Avoid the use
of extension cords. If they must be used on a temporary
basis, use 14-gauge or heavier cords.
The DS450 utilizes a compatible grounding system that
generally does not require a “ground lifter” adapter plug on
the AC power cord to minimize hum. The power cord on
your DS450 has a standard three-prong grounding plug to
provide maximum safety when it is connected to a ground-
ed wall receptacle. If there is any question regarding the
safety of grounding procedures, be certain to seek compe-
tent help with the installation. Do not substitute a lighter
gauge power cord for the one supplied with this unit.
If an electronic crossover or other AC powered equipment
is used with the amplifier it may be necessary to use
“ground lifter” adapters on the power plugs of that equip-
ment 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.
Single-Ended Operation
Single-ended inputs should be used with a preamplifier (or
electronic crossover, etc.) having single-ended outputs
which does
not
invert overall phase or polarity. When
using single-ended inputs, set two rear-panel toggles to SE
position. Disconnect any balanced cables.
Balanced Operation
Balanced inputs can be used with a preamplifier (or
electronic crossover, etc.) having balanced outputs. When
using the balanced inputs, set two rear-panel toggles to
BAL position. Disconnect any single-ended cables.
Installation
The amplifier may be installed in a ventilated cabinet;
observe the following guidelines to maximize the perfor-
mance and service of your amplifier.
With proper installation, the DS450 may be left on continu-
ously for maximum performance on demand; it will draw
approximately 55 watts of AC power at idle. However, the
DS450 has been designed and engineered to minimize any
“warm up” necessary for best sonics; generally, a half-hour
or 45 minutes of actual playing time will bring the amplifier
around to more than acceptable performance levels, with
some additional improvement noticeable over the next
hour or two. Warm-up characteristics will depend upon
ambient room temperature at start-up, the nature of the
installation and the resolving power of the associated
equipment.
Operate the DS450 only in a horizontal (upright) position.
Adequate airflow and proper cooling can be maintained
only if there is no restriction around the unit.
The five (5) non-marring feet provide adequate spacing and
mechanical damping only from a smooth, hard surface.
Never operate the unit while it is sitting on a soft, irregu-
lar surface such as a rug or carpet.
If the unit is to be operated in an enclosure such as an
equipment rack, make certain that adequate air flow above
and below the unit is provided. The “ambient” operating
temperature should never exceed 120º F or 49º C. Improper
installation will cause premature component failure and
will affect your warranty, as well as the service life of
the unit.
It is normal for the DS450 power amplifier to run lightly to
moderately warm to the touch. All components within are
operated at safe, conservative levels and will not be im-
properly affected, providing the requirements outlined
above are adhered to.
Remote Turn-on Connections
The DS450 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 IN jack on the rear of
the DS450. Two identical paralleled jacks are provided
to allow chaining connections to control two or more
DS450s or other equipment.
The +12V IN jack should be connected to the +12VDC
output of the master control system, using a continuous
+12VDC signal at 20mA per DS450 for the duration of
amplifier on-time. Do not use a momentary or data pulse
control signal.
Model DS450
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