Sony TC-K620 is a stereo cassette deck with a three-head system that allows instant monitoring of the recorded sound, bias control to achieve the best bias current for any tape, and the Dolby HX PRO system that improves the linearity of the tape's high-range response during recording. It also features an easy-to-read digital linear counter that shows the elapsed recording or playing time, the AMS function that provides easy access to a desired selection, and Dolby noise reduction. Its ports enable connections to amplifiers, tape decks, and headphones.