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CD player

From Wikipedia, the free encyclopedia

BERJAYA
A portable CD player

A CD player is an electronic device that plays audio compact discs, which are a digital optical disc data storage format. CD players were first sold to consumers in 1982. CDs typically contain recordings of audio material such as music or audiobooks. CD players may be part of home stereo systems, car audio systems, personal computers, or portable CD players such as CD boomboxes. Most CD players produce an output signal via a headphone jack or RCA jacks. To use a CD player in a home stereo system, the user connects an RCA cable from the RCA jacks to a hi-fi (or other amplifier) and loudspeakers for listening to music. To listen to music using a CD player with a headphone output jack, the user plugs headphones or earphones into the headphone jack.

Modern units can play audio formats other than the original CD PCM audio coding, such as MP3, AAC and WMA. DJs playing dance music at clubs often use specialized players with an adjustable playback speed to alter the pitch and tempo of the music. Audio engineers using CD players to play music for an event through a sound reinforcement system use professional audio-grade CD players. CD playback functionality is also available on CD-ROM/DVD-ROM drive-equipped computers as well as on DVD players and most optical disc-based home video game consoles.

History

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Sony CDP-101 from 1982, the first commercially released CD player for consumers
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Philips CD100 from 1983, the first commercially released CD player in the USA and Europe

American inventor James T. Russell is known for inventing the first system to record digital video information on an optical transparent foil that is lit from behind by a high-power halogen lamp.[1][2] Russell's patent application was first filed in 1966, and he was granted a patent in 1970. Following litigation, Sony and Philips licensed Russell's recording patents (then held by a Canadian company, Optical Recording Corp.) in the 1980s.[3][4][5]

The compact disc is not based on Russell's invention; it is an evolution of LaserDisc technology, where a focused laser beam is used that enables the high information density required for high-quality digital audio signals. Prototypes were developed by Philips and Sony independently in the late 1970s.[6] In 1979, Sony and Philips set up a joint task force of engineers to design a new digital audio disc. After a year of experimentation and discussion, the Red Book CD-DA standard was published in 1980. After their commercial release in 1982, compact discs and their players were extremely popular. Despite costing up to $1,000, over 400,000 CD players were sold in the United States between 1983 and 1984.[7] The success of the compact disc has been credited to the cooperation between Philips and Sony, who came together to agree upon and develop compatible hardware. The unified design of the compact disc allowed consumers to purchase any disc or player from any company and allowed the CD to dominate the at-home music market unchallenged.[8]

The Sony CDP-101, released in 1982, was the world's first commercially released compact disc player. It was originally sold only in Japan.[9]

Unlike early LaserDisc players, the first CD players already used laser diodes instead of larger helium-neon lasers.[10][11]

Digital audio laser-disc prototypes

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In 1974, Lou Ottens, director of the audio division of Philips, started a small group with the aim to develop an analog[12] optical audio disc with a diameter of 20 cm (7.9 in) and a sound quality superior to that of the vinyl record.[13] However, due to the unsatisfactory performance of the analog format, two Philips research engineers recommended a digital format in March 1974.[12] In 1977, Philips then established a laboratory with the mission of creating a digital audio disc. The diameter of Philips's prototype compact disc was set at 11.5 cm (4.5 in), the diagonal of an audio cassette.[12][14]

Heitaro Nakajima, who developed an early digital audio recorder within Japan's national public broadcasting organization NHK in 1970, became general manager of Sony's audio department in 1971. His team developed a digital PCM adaptor audio tape recorder using a Betamax video recorder in 1973. After this, in 1974, the leap to storing digital audio on an optical disc was easily made.[15] Sony first publicly demonstrated an optical digital audio disc in September 1976. A year later, in September 1977, Sony showed the press a 30 cm (12 in) disc that could play 60 minutes of digital audio (44,100 Hz sampling rate and 16-bit resolution) using MFM modulation.[16] In September 1978, the company demonstrated an optical digital audio disc with a 150-minute playing time, 44,056 Hz sampling rate, 16-bit linear resolution, and cross-interleaved error correction code—specifications similar to those later settled upon for the standard compact disc format in 1980. Technical details of Sony's digital audio disc were presented during the 62nd AES Convention, held on 13–16 March 1979, in Brussels.[16] Sony's AES technical paper was published on 1 March 1979. A week later, on 8 March, Philips publicly demonstrated a prototype of an optical digital audio disc at a press conference called "Philips Introduce Compact Disc"[17] in Eindhoven, Netherlands.[18]

Collaboration and standardization

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Sony executive Norio Ohga, later CEO and chairman of Sony, and Heitaro Nakajima were convinced of the format's commercial potential and pushed further development despite widespread skepticism.[19] As a result, in 1979, Sony and Philips set up a joint task force of engineers to design a new digital audio disc. Led by engineers Kees Schouhamer Immink[20] and Toshitada Doi, the research pushed forward laser and optical disc technology.[17]

Philips coined the term compact disc in line with another audio product, the Compact Cassette,[14] and contributed the general manufacturing process, based on video LaserDisc technology. Philips also contributed eight-to-fourteen modulation (EFM), which offers a certain resilience to defects such as scratches and fingerprints, while Sony contributed the error-correction method, cross-interleaved Reed–Solomon coding (CIRC). The Compact Disc Story,[12] told by a former member of the task force, gives background information on the many technical decisions made, including the choice of the sampling frequency, playing time, and disc diameter. The task force consisted of around four to eight persons,[21][22] though according to Philips, the compact disc was "invented collectively by a large group of people working as a team."[23]

First Red Book CDs and players

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Red Book was the first standard in the Rainbow Books series of standards.

The Japanese launch was followed in March 1983 by the introduction of CD players and discs to Europe[28] and North America (where CBS Records released 16 titles).[29] This event is often seen[by whom?] as the "Big Bang" of the digital audio revolution. The new audio disc was enthusiastically received, especially in the early-adopting classical music and audiophile communities, and its handling quality received particular praise. As the price of players gradually came down, and with the introduction of the portable Walkman, the CD began to gain popularity in the larger popular and rock music markets. The first artist to sell a million copies on CD was Dire Straits, with their 1985 album Brothers in Arms.[30] The first major artist to have his entire catalog converted to CD was David Bowie, whose 15 studio albums were made available by RCA Records in February 1985, along with four greatest hits albums.[31] In 1988, 400 million CDs were manufactured by 50 pressing plants around the world.[32]

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Sony CD Walkman D-E330

Further development and decline

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A JVC FS-SD5R CD player from the 1990s with a transparent plastic cover and blue backlight

The CD was planned to be the successor of the gramophone record for playing music, rather than primarily as a data storage medium, but from its origins as a format for music, its use has grown to encompass other applications. In 1983, following the CD's introduction, Immink and Braat presented the first experiments with erasable compact discs during the 73rd AES Convention.[33] In June 1985, the computer-readable CD-ROM (read-only memory) was introduced and, in 1990, the CD-Recordable, also developed by both Sony and Philips.[34]

By the early 2000s, the CD player had largely replaced the audio cassette player as standard equipment in new automobiles, with 2010 being the final model year for any car in the US to have a factory-equipped cassette player.[35]

7-disc CD changers were once made by NEC and Nakamichi[36] for PCs.

Meanwhile, with the advent and popularity of Internet-based distribution of files in lossily-compressed audio formats such as MP3, sales of CDs began to decline in the 2000s. For example, between 2000 and 2008, despite overall growth in music sales and one anomalous year of increase, major-label CD sales declined overall by 20%[37] – although independent and DIY music sales may be tracking better (according to figures released 30 March 2009), and CDs still continue to sell greatly.[38] As of 2012, CDs and DVDs made up only 34% of music sales in the United States.[39] In Japan, however, over 80% of music was bought on CDs and other physical formats as of 2015.[40]

Inner workings

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Some early optical computer drives are equipped with an audio connector and buttons for standalone CD playback functionality.[41]

Tray design types

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Tray loading

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A 1980s-era Denon CD player with the chassis cover removed to show the electronic and mechanical components.
An example of a Pioneer CD player's tray closing.

Sony released its CDP-101 CD player[42] in 1982 with a slide-out tray design for the CD. As it was easy to manufacture and to use, most CD player manufacturers stayed with the tray style ever since.[43][44]

Vertical loading

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During the launch of the first prototype Goronta CD player[45] by Sony at the Japanese Audio Fair in 1982, Sony showcased the vertical loading design. Although the Sony prototype design was never put into volume production, the concept was for a time adopted for production by a number of early Japanese CD player manufacturers, including Alpine/Luxman, Matsushita under the Technics brand, Kenwood and Toshiba/Aurex. For the early vertical loading players, Alpine sourced their AD-7100 player designs for Luxman,[46] Kenwood and Toshiba (using their Aurex brand). Kenwood added their Sigma Drive outputs to this design as a modification. A picture of this early design can be seen on the Panasonic website.[47]

Top loading

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Philips CD100 Player

In 1983, Philips, at the US and European launch of the CD format, showcased the first top-loading CD tray designs with their CD100 CD player.[48][49] (Philips audio products were sold as Magnavox in the US at the time.) The design had a clamp on the lid, which meant the user had to close it over the CD when it was placed inside the machine. Later, Meridian introduced their MCD high end CD player,[50] with Meridian electronics in the Philips CD100 chassis.

Top-loading was adopted on various equipment designs, such as mini systems and portable CD players, but among stereo component CD players, only a handful of top-loading models have been made. Examples include Luxman's D-500 and D-500X series[51] players and Denon's DP-S1,[52] both launched in 1993.

Pickup mechanisms

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Underside view showing a radial-type tracking mechanism with screw drive
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Philips swing arm optical mechanism
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The optical chip extracted from a CD player. The three dark rectangles are photosensitive, read the data from the disk and keep the beam focused. Electronic tracking, aided with the two photodiodes at the sides, keeps the laser beam centered on the middle of the data track.

Two types of optical tracking mechanisms exist:

  • The swing-arm mechanism, originally designed by Philips[53] – the lens moves at the end of an arm, in a manner similar to the tone arm assembly of a record player. Used in the earliest Philips CD players and later replaced with cheaper radial mechanisms.
  • The radial mechanism, designed by Sony, which is the one used in most CD players in the 2000s – the lens moves on a radial rail being driven by a rotating gear from a motor or a linear magnetic assembly. The motor or linear magnetic assembly consists of a solenoid mounted to the moving laser assembly, wound over a permanent magnetic field attached to the base of the mechanism. It is also known as three-beam linear tracking.
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Philips one-beam laser assembly

The swing-arm mechanism has a distinctive advantage over the other in that it does not skip when the rail becomes dirty. The swing arm mechanisms tend to have a much longer life than their radial counterparts.[citation needed] The main difference between the two mechanisms is the way they read the data from the disc. The swing-arm mechanism uses a magnetic coil wound over a permanent magnet to provide the tracking movement to the laser assembly in a similar way a hard drive moves its head across the data tracks. It also uses another magnetic movement mechanism attached to the focusing lens to focus the laser beam on the disc surface. By operating the tracking or the focus actuators, the laser beam can be positioned on any part of the disc. This mechanism employs a single laser beam and a set of four photodiodes to read, focus, and keep track of the data coming from the disc.[54]

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Sharp laser optical assembly. All six focusing and tracking coils can be seen.

The linear tracking mechanism uses a motor and reduction gears to move the laser assembly radially across the tracks of the disc, and it also has a set of six coils mounted in the focusing lens over a permanent magnetic field. One set of two coils moves the lens closer to the disc surface, providing the focusing motion, and the other set of coils moves the lens radially, providing a finer tracking motion. This mechanism uses the three-beam tracking method in which a main laser beam is used to read and focus the data track of the disc using three or four photodiodes, depending on the focus method, and two smaller beams read the adjacent tracks at each side to help the servo keep the tracking using two more helper photodiodes.[55]


Portable CD players

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Small portable players

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An early portable player, a Sony Discman model D-121
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A Philips portable CD player disassembled
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Attached controller to facilitate playback control

A portable CD player is a portable audio player used to play compact discs. Portable CD players are powered by batteries and they have a 1/8" headphone jack into which the user plugs a pair of headphones. The first portable CD player released was the D-50 by Sony.[56] The D-50 was made available on the market in 1984,[57] and adopted for Sony's entire portable CD player line.

In 1998, portable MP3 players began to compete with portable CD players. After Apple Computer entered the music player market with its iPod line, within ten years it became the dominant seller of portable digital audio players, "...while former giant Sony (maker of the [portable] Walkman and [CD] Discman [was] struggling."[58] This market shift was initiated when the first portable digital audio player, the Rio digital music player, was introduced. The 64 MB Rio MP3 player enabled users to store about 20 songs.[59] One of the benefits of the Rio over portable CD players was that since the Rio had no moving parts, it offered skip-free playback.[59] Since 1998, the price of portable digital audio players has dropped and the storage capacity has increased significantly. In the 2000s, users can "carry [their] entire music collection in a [digital audio] player the size of a cigarette package."[59] The 4 GB iPod, for example, holds over 1,000 songs.[59] By the early 2010s, MP3 players began to decline in popularity,[60] in favour of downloading music on platforms such as iTunes, and later streaming music on platforms such as Spotify, Apple Music, and YouTube Music.[61][62][63]

Boomboxes

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A Sony CD boombox from 2005

A boombox is a common term for a portable cassette and AM/FM radio that consists of an amplifier, two or more loudspeakers and a carrying handle. Beginning in the 1990s, boomboxes typically included a CD player. The boombox CD player is the only type of CD player that produces sound audible by the listener independently, without the need for headphones or an additional amplifier or speaker system. Designed for portability, boomboxes can be powered by batteries as well as by line current. The boombox was introduced to the American market during the mid-1970s. The desire for louder and heavier bass led to bigger and heavier boxes; by the 1980s, some boomboxes had reached the size of a suitcase. Most boomboxes were battery-operated, leading to extremely heavy, bulky boxes.[64]

Most boomboxes from the 2010s typically include a CD player compatible with CD-R and CD-RW, which allows the user to carry their own music compilations on a higher fidelity medium. Many also permit iPod and similar devices to be plugged into them through one or more auxiliary input jacks. Some also support formats such as MP3 and WMA. Another modern variant is a DVD player/boombox with a top-loading CD/DVD drive and an LCD video screen in the position once occupied by a cassette deck.[65]

DJ equipment

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This example of a CD player used by DJs is the Denon DN-2500 dual CD player, on the right side of the picture. A Behringer VMX-200 DJ mixer is also shown in the left side, in the foreground.

Disc jockeys (DJs) who are playing a mix of songs at a dance club, rave, or nightclub create their dance mixes by having songs playing on two or more sound sources and using a DJ mixer to transition seamlessly between songs. In the 1970s disco era, DJs typically used two record players.[66] From the 1980s to the 1990s, two compact cassette players became a popular sound source for DJs.[67]

See also

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References

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  1. ↑ U.S. patent 3,501,586 Analog to digital to optical photographic recording and playback system, March 1970.
  2. ↑ U.S. patent 3,795,902 Method and apparatus for synchronizing photographic records of digital information, March 1974.
  3. ↑ Brier Dudley (29 November 2004). "Scientist's invention was let go for a song". The Seattle Times. Retrieved 24 July 2014.
  4. ↑ "Inventor and physicist James Russell '53 will receive Vollum Award at Reed's convocation" (Press release). Reed College public affairs office. 2000. Archived from the original on 9 October 2013. Retrieved 24 July 2014.
  5. ↑ "Inventor of the Week - James T. Russell - The Compact Disc". MIT. December 1999. Archived from the original on 17 April 2003.
  6. ↑ "The History of the CD". Philips Research. Retrieved 7 June 2014.
  7. ↑ Rasen, Edward (May 1985). "Compact Discs: Sound of the Future". Spin. Retrieved 9 January 2016.
  8. ↑ Archived at Ghostarchive and the Wayback Machine: Introducing the amazing Compact Disc (1982). Australian Broadcasting Corporation. 10 June 2015. Retrieved 9 January 2016 – via YouTube.
  9. ↑ "Sony Global - Product & Technology Milestones-Home Audio". www.sony.net. Retrieved 21 January 2018.
  10. ↑ Shimizu, H. (2019). General Purpose Technology, Spin-Out, and Innovation: Technological Development of Laser Diodes in the United States and Japan. Springer. pp. 138–139. ISBN 9789811337147.
  11. ↑ Origins and Successors of the Compact Disc. Philips Research. Vol. 11. Springer. 2009. pp. 14, 141. doi:10.1007/978-1-4020-9553-5. ISBN 978-1-4020-9552-8.
  12. 1 2 3 4 Kees A. Schouhamer Immink (1998). "The CD Story". Journal of the Audio Engineering Society. 46: 458–465. Archived from the original on 4 November 2014. Retrieved 21 December 2014.
  13. ↑ Why CDs may actually sound better than vinyl, Chris Kornelis, 27 January 2015
  14. 1 2 Peek, Hans B. (January 2010). "The Emergence of the Compact Disc". IEEE Communications Magazine. 48 (1): 10–17. doi:10.1109/MCOM.2010.5394021. ISSN 0163-6804. S2CID 21402165.
  15. ↑ McClure, Steve (8 January 2000). "Heitaro Nakajima". Billboard. p. 68. Retrieved 4 November 2014.
  16. 1 2 "A Long Play Digital Audio Disc System". AES. March 1979. Retrieved 14 February 2009.
  17. 1 2 "How the CD Was Developed". BBC News. 17 August 2007. Retrieved 17 August 2007.
  18. ↑ "Philips Compact Disc". Philips. Archived from the original on 19 March 2009. Retrieved 14 February 2009.
  19. ↑ "Sony chairman credited with developing CDs dies", Fox News, 24 April 2011, retrieved 14 October 2012
  20. ↑ K.A. Schouhamer Immink (2018). "How we made the compact disc". Nature Electronics. 1. Retrieved 2018-04-16. An international collaboration between Philips and the Sony Corporation lead to the creation of the compact disc. The author explains how it came about
  21. ↑ Kees A. Schouhamer Immink (2007). "Shannon, Beethoven, and the Compact Disc". IEEE Information Theory Newsletter: 42–46.
  22. ↑ Knopper, Steve (7 January 2009). Appetite for Self-Destruction: The Rise and Fall of the Record Industry in the Digital Age. Free Press/Simon & Schuster. ISBN 9781416552154.
  23. ↑ "The Inventor of the CD". Philips Research. Retrieved 16 January 2009.{{cite web}}: CS1 maint: deprecated archival service (link)
  24. ↑ "Optical Recording" (Press release). Royal Philips Electronics.
  25. ↑ Bilyeu, Melinda; Hector Cook; Andrew Môn Hughes (2004). The Bee Gees:tales of the brothers Gibb. Omnibus Press. p. 519. ISBN 978-1-84449-057-8.
  26. ↑ "And 25 Years Ago Philips Introduced the CD". GeekZone. Retrieved 11 January 2008.
  27. ↑ "Sony History: A Great Invention 100 Years On". Sony. Archived from the original on 2 August 2008. Retrieved 28 February 2012.
  28. ↑ Philips celebrates 25th anniversary of the Compact Disc, Philips Media Release, 16 August 2007. Retrieved 6 October 2013.
  29. ↑ Kaptains, Arthur (5 March 1983). "Sampling the latest sound: should last a lifetime". The Globe and Mail. Toronto. p. E11.
  30. ↑ Maxim, 2004
  31. ↑ The New Schwann Record & Tape Guide Volume 37 No. 2 February 1985
  32. ↑ MAC Audio News. No. 178, November 1989. pp 19-21 Glenn Baddeley. November 1989 News Update. Melbourne Audio Club Inc.
  33. ↑ Immink, Kees A.; Braat, Joseph J. (August 1984). "Experiments Toward an Erasable Compact Disc". Journal of the Audio Engineering Society. 32 (7/8): 531–538. Retrieved 26 October 2014.
  34. ↑ The world's first CD-R was made by the Japanese firm Taiyo Yuden Co., Ltd. in 1988 as part of the joint Philips-Sony development effort.
  35. ↑ Williams, Stephen (4 February 2011). "For Car Cassette Decks, Play Time Is Over". New York Times. Retrieved 18 July 2012.
  36. ↑ "Nakamichi MBR-7 7 Disc CD-Rom Changer - Peripheral - Computing History". Computing History.
  37. ↑ Smith, Ethan (2 January 2009). "Music Sales Decline for Seventh Time in Eight Years: Digital Downloads Can't Offset 20% Plunge in CD Sales". Wall Street Journal. Retrieved 4 March 2009.
  38. ↑ "CD Baby Payouts Surge". Indiemusicstop.wordpress.com. 30 March 2009. Archived from the original on 18 July 2011. Retrieved 1 December 2009.
  39. ↑ "Buying CDs continues to be a tradition in Japan - Tokyo Times". 23 August 2013. Archived from the original on 20 December 2016. Retrieved 21 January 2018.
  40. ↑ Sisaro, Ben (11 June 2015). "Music Streaming Service Aims at Japan, Where CD Is Still King". New York Times.
  41. ↑ "NEC MultiSpin 6X CDR-1350A - CD-ROM drive - IDE - internal Specs - CNET". Archived from the original on 2021-07-19. Retrieved 2021-07-19.
  42. ↑ "CDP-101 The first Compact Disc Audio CD Player from 1982". 2007. Retrieved 2007-02-05.[permanent dead link]
  43. ↑ "Pioneer Stable Platter Mechanism" (in Japanese).
  44. ↑ "Pioneer Stable Platter Mechanism".
  45. ↑ "Sony History". 2007. Archived from the original on 2006-11-30. Retrieved 2007-02-05.
  46. ↑ "Luxman DX-104 CD Player". 2007. Retrieved 2007-02-17.
  47. ↑ "Panasonic History - Innovative Products - 1982 - CD Player". 2007. Archived from the original on 2008-10-06. Retrieved 2007-02-05.
  48. ↑ Philips CD100 Player - Marantz-Philips Nederlands website
  49. ↑ The history of the CD - The introduction, Philips Research.
  50. ↑ "Meridian CD History". 2007. Archived from the original on 2007-02-04. Retrieved 2007-02-05.
  51. ↑ "Luxman D-500X (in Japanese)". 2007. Archived from the original on 2007-07-17. Retrieved 2007-02-05.
  52. ↑ "Denon Museum - Model History - 1993 - DP-S1 (in Japanese)". 2007. Archived from the original on 2007-02-04. Retrieved 2007-02-05.
  53. ↑ "Swing-arm mechanism description". Siber-sonic.com. Retrieved 2012-05-06.
  54. ↑ Philips CD100 Service Manual
  55. ↑ Sony CDP-101 Service Manual
  56. ↑ Lungu, R. (2008-11-27), History of the Portable Audio Player, archived from the original on May 2, 2012
  57. ↑ "Sony Celebrates Walkman 20th Anniversary". Sony Press Release. Retrieved 2009-05-04.
  58. ↑ Dyer, Jeffrey H.; Godfrey, Paul; Jensen, Robert; Bryce, David (2005). Strategic Management: Concepts and Cases. Wiley Global Edition. p. 5.
  59. 1 2 3 4 Fries, Bruce; Fries, Marty (2005). Digital Audio Essentials. O'Reilly Media Inc. pp. 112–113. ISBN 9780596008567.
  60. ↑ Elmore, J. (2024). The Revival of a Bygone Era: Are MP3 Players Still Manufactured? [online] TheTechyLife. Available at: https://thetechylife.com/are-mp3-players-still-manufactured/ [Accessed 23 Jan. 2025].
  61. ↑ Rosenblatt, B. (n.d.). The Short, Unhappy Life Of Music Downloads. [online] Forbes. Available at: https://www.forbes.com/sites/billrosenblatt/2018/05/07/the-short-unhappy-life-of-music-downloads/.
  62. ↑ Cross, Alan (19 March 2023). "How much longer will we be able to buy digital downloads of songs?". Global News. Retrieved 11 May 2026.
  63. ↑ "The Rise and Fall of Music Downloads: A Retrospective".
  64. ↑ Kelly, Frannie (22 April 2009). "A Eulogy For The Boombox". NPR.org. Retrieved November 16, 2011.
  65. ↑ "Go Video brings LCD to boombox". Ubergizmo.com. 2007-08-15. Retrieved 2010-06-22.
  66. ↑ Katz, Mark. Capturing Sound: How Technology Has Changed Music. University of California Press, 2010. p. 127
  67. ↑ "Art and History of DJ Mixing by Alex Cosper". www.playlistresearch.com. Retrieved 21 January 2018.
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