General Instructions - Harman Kardon PM655 Owner's Manual

FEATURES
MHCC (High-instantaneous Current Capability)
Recent studies have shown that while reproducing dynamic
music signals the instantaneous impedances of nearly all
loud-speakers drop to less than one third of the nominal
ratings. These low instantaneous impedances typically
require 3 to 6 times more current than an 8 Ohm resistive
load. Reduced dynamic range and increased distortion will
result if the amplifier cannot provide these higher currents.
For this reason, the PM655 was designed to provide 45
amperes of instantaneous Current.
WUltrawide Bandwidth
The bandwidth of this unit is exceptionally wide and inde-
pendent of negative feedback. This improves transient
accuracy and phase linearity.
Mi Low Negative Feedback
This unit has been designed to have low distortion and wide
bandwidth without high negative feedback. This further
improves its dynamic accuracy.
Dual RIAA Phono Equalization
The phono section employs Harman Kardon's unique dual
RIAA equalization circuitry. RIAA equalization is used in both
the open-loop and closed-loop signal path (with and
without negative feedback). This permits the application of
constant low-level negative feedback throughout the audio
range.
@ Discrete Component Circuitry
In order to achieve the above goals, all discrete electronic
circuitry has been employed. All available integrated circuits
could not provide this high level of performance.
@ Sophisticated Electronic Protection
Harman Kardon engineers developed a unique protection
system that permits high instantaneous current to be driven
into speaker systems but protects the amplifier from short-
circuited or damaged speakers and wires. This protection
system in no way limits amplifier output voltage or current
during music reproduction, and therefore has no negative
effect on sound quality.
Moving Coil Cartridge Amplifier
A high sensitivity, low noise amplifier is provided. This
permits the direct input of most moving coil cartridges.
@ Capacitance Trim Selector
This feature enables precise impedance matching between
moving magnet type cartridges and the phonocircuitry. The
widest, flattest frequency response possible can be
obtained from any high quality phono cartridge.
MPre-out/Main-in Switch
This feature allows independent use of the preamplifier and
main (power) amplifier sections. With this switch in the
"integrated" position, the preamplifier section is internally
connected to the main (power) amplifier. By depressing this
switch to the "separate" position, the preamplifier output
and main (power) amplifier input jacks on the rear panel
become active.
@Bass Contour
Bass contour is an exclusive Harman Kardon feature which
provides two major benefits: it can equalize and restore the
low frequency response of small loud-speakers, and it can
be used in place of conventional loudness contour. But
unlike conventional bass boost circuits, Harman Kardon's
bass contour also includes a phase correction circuit that
maintains clear, natural sound.
GENERAL INSTRUCTIONS
Always Use at 120V AC
This unit is designed for operation with 120V AC. Connect
only to domestic AC outlets. Never connect the unit to an
outlet supplying a higher voltage. This may create a fire
hazard.
Handle the Power Cord Gently
@Do not disconnect the plug from the AC outlet by pulling
the cord: always pull the plug itself. Pulling the cord may
break the wire.
@/f you do not intend to use your unit for any considerable
length of time, disconnect the piug from the AC outlet.
@Do not place furniture or other heaw objects on the cord,
and avoid dropping heavy objects on it. Also do not make a
knot in the power cord. Notonly may the cord be damaged, it
can also cause a short circuit and a consequent fire hazard.
Place of Installation
Place your unit on a firm and level surface. Avoid installing
your unit under the following conditions:
> Moist or humid places.
»Places exposed to direct sunlight or close to heating
equipment.
> Extremely cold locations such as those in the direct draft
from an air conditioner.
> Places subject to excessive vibration or dust.
> Poorly ventilated places.
Do not cover the ventilation slots on the top of the unit. This
will cause the temperature inside the unit to rise, which can
eventually effect the reliability of your unit.
Moving the Unit
Before moving the unit, be sure to unplug the power cord
from the AC outlet and disconnect the interconnection
cords to other units.
Do Not Open the Cabinet
To prevent fire or shock hazard, do not tamper with internal
components for inspection or maintenance. Harman
Kardon does not guarantee against performance degrada-
tion resulting from any modification.
If water, a hairpin or wire accidentally enters the unit,
immediately unplug the power cord from the AC outlet to
prevent shock and consult an authorized Harman Kardon
service station. If you use the unit under this condition, it
may cause a fire or shock hazard.
Cleaning
When the unit gets dirty, wipe it with a soft dry cloth. If
necessary, wipe it with a soft cloth dampened with mild
soapy water and then wipe with a dry cloth.
Never use benzine, thinner, alcohol or other volatile agent,
and avoid spraying an insecticide near the unit.