The main features of the Harman Kardon HK2500 are: 2 heads, analog 3 digit tape counter, manual tape type selection with support for normal, chrome and ferro-chrome tapes with additional manual equalization selection, belt driven single-capstan transport.
Typical front loading cassette deck with the cassette compartiment located on the left side of the deck. Tape eject is operated mechanically and the cassette needs to be placed with the side to be played facing forward in the cassette well.
Level meters used on the HK2500 are analog needle VU reading meters. Mechanical transport controls for reliable HK2500 transport function selection.
The Dolby-B system reduces tape hiss on tapes recorded on the HK2500 by as much as 10 dB at the highest frequencies. A Subsonic filter is provided in the HK2500 to prevent infrasonic signals generated when playing a warped record. These signals can upset the Dolby system and prevening it from functioning properly.
To make live recordings this deck has 2 microphone inputs to connect microphones with a jack connector. For undisturbed listening a jack connector for a pair of stereo headphones is supplied. Connection to other audio components for plaback can be achieved by a RCA cable and recording from a source by a RCA cable.