Compact Disc 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. CD players are often a part of home stereo systems, car audio systems, and personal computers. With the exception of CD boomboxes, most CD players do not produce sound by themselves. Most CD players only produce an output signal via a headphone jack and/or RCA jacks. To listen to music using a CD player with a headphone output jack, the user plugs headphones or earphones into the headphone jack. To use a CD player in a home stereo system, the user connects an RCA cable to the RCA jacks or other outputs and connects it to a hi-fi (or other amplifier) and loudspeakers for listening to music. They are also manufactured as portable devices, which are battery powered and typically used with headphones.

Modern units can play other formats in addition to PCM audio coding used in CDs, 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 valuable on CD-ROM/DVD-ROM drive equipped computers as well as on DVD players and CD-ROM/DVD-ROM based game consoles.

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