6 REAR-PANEL CONNECTIONSRear-Panel Connections Digital OutputAudio OutputsRemote Control InputRemote Control OutputAC Power CordCoaxial and Optical Digital InputsHRS-LINK Output Digital Output: Connect this jack to thecoaxial or optical digital input of an externaldigital-to-analog converter for direct access to thedigital signals of the CD player or the externaldigital audio source. DO NOT connect this jack tothe standard audio inputs of any device. Audio Outputs: Connect these jacks to theCD audio inputs of your receiver, surroundprocessor or preamplifier.If your amplifier features balanced XLR inputs,you may use the XLR outputs instead. Soundquality via balanced connection is usually moredynamic, with even better signal-to-noise ratio.Pin configuration for the XLR Outputs: Pin 1 isGround, Pin 2 is Plus/Hot, Pin 3 is Minus/Cold. Remote Control Input:Connect the output of a remote infrared sensoror the remote control output of another compati-ble Harman Kardon product. This will enable theremote control system to operate even when thefront panel Remote Sensor 3 is blocked.It will also allow use of the CD player withoptional, external control systems. Remote Control Output: Connect thisjack to the input of another compatibleHarman Kardon remote controlled device tohave the remote sensor on the CD player pro-vide signals to other products. AC Power Cord: Connect this plug to anAC outlet. If the outlet is switch controlled, makecertain that the switch is in the ON position. Coaxial and Optical Digital Inputs:Connect these jacks to the coaxial or opticaldigital output of an external audio source. Thiswill enable you to have the digital-to-analogconversion of that source done by the high-grade audiophile digital-to-analog convertors inthe HD 990 rather than the (older ones) in theexternal source, for better audio quality. HRS-LINK jack: The special High-ResolutionSynchronization Link cable (optional) connects tothe HRS jack on the matching HK 990 amplifier(or other compatible HK amplifiers) to attain aneven higher quality of sound. You need only con-nect the HRS-Link Cable for complete synchro-nization and audio. No further cable is neces-sary.