Elcaset is a short-lived audio format jointly developed by Sony, Panasonic, and Teac in 1976, building on an idea introduced 20 years earlier in the RCA tape cartridge.

For most people, the quality of compact cassettes was adequate, and the benefits of the expensive Elcaset system limited.

Audiophiles turned away from Elcaset and towards high-end compact cassette decks from companies like Nakamichi, which began making very high-quality tape decks using the compact audio cassette in late 1973, even three years before the Elcaset was released.

Elcaset was featured at the 1978 Northern Audio Fair in Harrogate, Yorks (three hotels along Ripon Road) and was to be seen at UK audio retailers in that year but promotion withered towards the end of that year and Elcaset machines were disappearing during early 1979.

[4] Like the earlier RCA tape cartridge, it contained 1⁄4 inch (6.4 mm) tape running at 3+3⁄4 inches per second (9.5 cm/s), twice the width and twice the speed of a compact cassette, providing greater frequency response and dynamic range with lower high-frequency noise than the compact cassette.