Koss Sterophones

 Koss Corporation founder John Koss shares his behind-the-scenes story of inventing the world's first SP/3 stereophone in 1958, and the emotional thrill of being "enclosed in the music" thanks to his innovation. In 1958, John C. Koss teamed up with engineer Martin Lange, Jr. to develop a portable stereo phonograph player with side-wing speakers. The pair demonstrated their new stereo record player at a Wisconsin audio show. One of the product's unique features was a privacy switch, which allowed listeners to hear music by plugging in the world's first SP/3 stereophone. The stereophones were intended to be an accessory to demonstrate the high-fidelity stereo sound that the portable phonograph player delivered.