Harman Kardon RPM665 Owners Manual - Page 3

FEATURES ■ HCC (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 wi l l result if the amplifier cannot provide these higher currents. For this reason, the PM665 was designed to provide 60 amperes of instantaneous current. ■ Ultrawide Bandwidth The bandwidth of this unit is exceptionally wide and independent of negative feedback. This improves transient accuracy and phase l inearity. ■ 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 shortcircuited or damaged speakers and wires. This protection system in no way l imits 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 phono circuitry. The widest, flattest frequency response possible can be obtained from any high quality phono cartridge. ■ Pre-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 smal l 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 1 20V 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 pul l the plug itself. Pul l ing the cord may break the wire. •If you do not intend to use your unit for any considerable length of time, disconnect the plug from the AC outlet. •Do not place furniture or other heavy objects on the cord, and avoid dropping heavy objects on it. Also do not make a knot in the power cord. Not only 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 instal l ing 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 degradation 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. 2