Apple Wiki
Apple Wiki
Apple BASIC cassette for Apple I

A cassette tape containing Apple BASIC for the Apple-1 computer

The Compact Cassette or Musicassette (MC), also commonly called the tape cassette,[1] cassette tape, audio cassette, or simply cassette, is an analog magnetic tape recording format developed by a team led by Lou Ottens at Royal Philips in Hasselt, Belgium. It was introduced in September 1963 for audio recording and playback. It was also a popular data storage medium for early microcomputers. Compact Cassettes can be obtained with existing content as a pre-recorded cassette, or as a fully-recordable "blank" cassette. Both forms are reversible by the user.[2]


Compact Cassettes contain two miniature spools, between which the magnetically coated, polyester-type plastic film (magnetic tape) is passed and wound.[3] These spools and their attendant parts are held inside a protective plastic shell which is 4 by 2.5 by 0.5 inches (10 cm × 6.3 cm × 1.3 cm) at its largest dimensions. The tape itself is commonly referred to as "eighth-inch" tape, supposedly 1⁄8 inch (3.17 mm) wide, but it is slightly larger: 0.15 inches (3.81 mm).[4] Two stereo pairs of tracks (four total) or two monaural audio tracks are available on the tape; one stereo pair or one monophonic track is played or recorded when the tape is moving in one direction and the second (pair) when moving in the other direction. This reversal is achieved either by flipping the cassette, or by the reversal of tape movement ("auto-reverse") when the mechanism detects that the tape has come to an end.[5]


Compact cassette technology was originally designed for dictation machines, but improvements in fidelity led to it supplanting stereo 8-track cartridges and reel-to-reel tape recordings in most non-professional applications.[6] Its uses ranged from portable audio to home recording. The first monaural cassette player designed for use in car dashboards was introduced in 1968. From the early 1970s to the mid-2000s, the cassette became one of the two most common formats for prerecorded music, first alongside the LP record and later the compact disc (CD).[7]

Data recording[]

In November 1975, Byte magazine held a symposium in Kansas City, Missouri to establish a standardized method of recording data from microcomputers onto readily available audiocassettes. Data was modulated (like a modem) into an audio signal that could be transmitted to the tape recorder. This method became the Kansas City standard, also called the Byte standard, which initially operated at 300 baud, with faster rates being implemented later.[8]

Apple Computer[]

Apple Checkbook 1 cassette

The slow speed of this cassette led to the creation of the Disk II.

The first products from the Apple Computer Company to utilize the cassette tape format were the Apple-1 Cassette Interface and Apple BASIC for the Apple-1 computer, all designed by co-founder Steve Wozniak in 1976.[9] The cassette interface transmitted data to and from the recorder at the rate of 1200 baud.[10] Apple recommended Panasonic or other premium tape recorders at or above the $40 price point for reliable data storage.[11] The Panasonic model available at the time was the RQ-309DS.[12]

The Apple II was released in June 1977 with built-in cassette inputs and outputs.[13] Cassettes were a popular software delivery medium for Apple II series computers through 1982.[14] However, Wozniak's own development of the Disk II drive led to cassettes being replaced by floppy disks as Apple's primary data storage format.[15] The Apple IIc was introduced in 1984 without a cassette interface.[16]


  1. Norelco Carry Corder 150 operating manual. Philips USA (1971).
  2. Learn about Tabs-In or Tabs-Out shells and leaders. Archived from the original on 9 August 2017. Retrieved on 9 August 2017.
  3. How Tape Recorders Work. HowStuffWorks (April 2000). Retrieved on 10 October 2015.
  5. "International standard IEC 60094-7: Magnetic tape sound recording and reproducing systems", International Electrotechnical Commission, Geneva. 
  6. "Magnetic Tape Recording", Van Nostrand Reinhold. 
  7. "Magnetic Recording: The First 100 Years", The Institute of Electrical and Electronics Engineers. 
  8. The Kansas City Standard by Mark VandeWettering, Brainwagon. 2011-07-22.
  9. the Apple-1 Cassette Interface Card by SpeedyG, / Applefritter. 2013-04.
  10. Peripherals by Achim Baqué, Apple-1 Registry. 2018-03-18.
  11. Apple-1 Cassette Interface manual (PDF) by the Apple Computer Company, 1976.
  12. Peripherals by Achim Baqué, Apple-1 Registry. 2018-03-18.
  13. Apple II Cassette Interface by Krest, 2005-08-17.
  14. Antoine's collection of Apple cassettes by Antoine Vignau, Brutal Deluxe Software. 2020-11-24.
  15. Markoff, John. "An 'Unknown' Co-Founder Leaves After 20 Years of Glory and Turmoil", The New York Times, September 1, 1997. Retrieved on February 4, 2011. 
  16. Apple IIc (//c), MCbx Old Computer Collection. Accessed 2021-03-13.

External links[]

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