Anatomy of a CD Player

An essential mechanism for all CD players is the entry point of the CD into the player. The most common type of insertion technique is a slide-out tray design. Sony first developed this technique, and it's largely been incorporated by other manufacturers into their machines.

Slot loading is another popular loading mechanism, notably integrated into the Sony Playstation 3, and a large selection of car cd players. With slot loading no tray is popped out, instead a motor assists a user to insert and remove a CD.

Then there is the components. A drive motor is needed to rotate / spin the disc, a CD is spun faster than a traditional LP vinal record is. At between 250 and 450 revolutions every minute of play.

A lens system then uses a laser and sensor to read data from the compact disc, and a mechanism helps to place the lens at the correct focus length. This placement mechanism either uses a rail with a swing arm, like on a turntable, or uses a rail with a radial design. While the swing arm technique is more reliable, it's also more expensive, therefore not as popular.

Most CD players incorporate a small LCD interface display. The LCD interface will display the track number and time, and sometimes the composer of the music. The control interface should also include a small panel of buttons, play, stop, pause, spin forward, spin rewind, track forward, and track rewind being standard functions.

CD changer mechanisms have also widely been integrated into CD players. This mechanism works by using a cartridge which can hold and load between three to twelve discs.

The CD player can then select which disc to load, play or remove. The aim of the mechanism is to save a user the effort of getting up from his/her chair to continually change CDs.

The internal cartridge system is the most widely integrated CD changer technique, largely due to it's space saving, and offering the most disc storage. But, carousel changers do exist, usually in large midi systems. The carousal usually holds three, five or seven discs. However, Juke Boxes are an example of a large scale carousal changing system.