Harman Kardon HK 990 Owners Manual - Page 4

HK 990 Congratulations on your choice of the ­Harman Kardon® HK 990 Integrated Amplifier. In order to obtain the best performance from this integrated amplifier, please be sure to read this owner's manual and use your integrated amplifier only in accordance with its instructions. In terms of raw power, the HK 990 is the most muscular amplifier ever to carry the Harman Kardon name, more than capable of driving the most demanding loudspeaker loads without breaking a sweat. But the HK 990's awesome power is nothing if not highly refined, extending beyond watts and amps. With a choice of discrete optical or coaxial inputs or an analog-only signal path, as well as fourth-generation Real-Time Linear Smoothing (RLS IV), 2.2-channel EzSet / EQ™ room optimization, dual subwoofer outputs and an audiophile-quality phono preamp section, the HK 990 offers a combination of features you will find irresistible. Others, of course, may simply hunger for all that power. We understand completely. The special features of this unit include: •• High-current capability to provide the instantaneous current necessary to drive and control nearly any loudspeaker system precisely •• Ultrawide-bandwidth amplifier design for improved transient accuracy and phase linearity •• Low negative feedback for further improved dynamic accuracy •• Use of discrete electronic circuitry to provide the highest performance level •• Dual-path technology for pure analog or pure digital audio processing within the same product •• EzSet/ EQ room optimization for quick and accurate system setup, optimized for two channels and two subwoofers •• Symmetric (balanced) XLR analog inputs for lower noise levels and higher signal-tonoise performance •• RLS IV digital-to-analog conversion technology, with dual conversion using two stereo AD1955 high-grade DACs in dual mono configuration •• HRS link for Harman Kardon CD players to lock themselves to the external clock of the amplifier for a jitter-free connection, similar to having CD playback inside the amplifier •• Dual differential input stages with their own high-voltage supply, resulting in high gain and low noise as well as high channel separation •• Cascoded predriver stage to reduce high-frequency distortion, allowing crystal-clear high frequencies, free from any harsh sound •• Thermal Tracking Mechanism using ThermalTrak™ output stage transistors that include internal temperature sensors to bias the current of the output stage in real time •• Sophisticated electronic-protection circuitry to guard the amplifier from short-circuit or from damaged speakers and wires, without impairing sound quality, by using current limiting or output relays •• DC servo to ensure that the DC level of the amplifier output will stay within a specified limit at any condition •• Multiple protection circuits to switch the amplifier off in case overcurrent, overvoltage, overtemperature or DC protection is detected •• Dual toroidal transformers and up to 15,000μF of supply filtering per channel for high channel separation and tight bass control, even with low-impedance loads •• Dual-line dot-matrix display •• Record out available in both digital and analog domains (two analog outputs and one coaxial digital output) •• A/B speaker switching •• IR remote extension jacks for control of the amplifier when placed in a cabinet •• Harman Kardon system remote for control of compatible Harman Kardon CD players and tuners Accessory List •• Owner's Manual •• Remote Control + 4 AAA batteries •• EzSet microphone •• Power cord 4 Introduction