Music’s Pre-Vinyl History
Music has been a part of human history since the beginning of mankind. Initially, one had to be in the presence of the musician in order to hear the piece being played. With no way to reproduce or transport the songs, music was an entirely live experience taking place right then and there for the audience. Sheet music was invented in the 15th century as a method of notating exactly which notes should be played and for how long, enabling other musicians to replay what the composer created. Then, one orchestra could play the same song as another one across the country, but a live performance was still required to actually turn those notes into audible music.
In 1877, Thomas Edison advanced the idea of the phonautograph with his own invention called a phonograph, which allowed the device to replay the recorded sound (Fig. 2). His invention followed the same basic principles as Scott de Martinville’s device, using a stylus moved by a vibrating membrane to etch waveforms into a rotating cylinder.
The vinyl albums that many are familiar with today stemmed from this evolution of mechanical sound reproductions. The gramophone of 1889 replaced the rotating cylinder with a flat vinyl disc rotated beneath the recording needle. This change essentially finalized the now-common disc design seen in records everywhere. In fact, even today many people are still snatching up records wherever they can find them because of the high sound quality and accompanying collector’s booklets .
The spiral grooves are the key to reproducing the recorded sound and replaying it for the user. The record is placed on a turntable (Fig. 4), a flat surface with a rotating shaft in the center and a stylus similar to that found on a phonograph. As the turntable rotates the disc at a constant speed (decided based on the type of record), the stylus tracks the spiral grooves, vibrating with the fine inscriptions recorded into the lacquer (Fig. 5). These vibrations are transmitted back up the stylus and amplified by a tightened membrane, producing sound into a cone-shaped horn (Fig. 3).
Data is read off the CD using a laser. As the disc spins, the laser shines on the disc and reflects back into a sensor (Fig. 6). If the laser shines on a bump, it scatters away from the sensor, registering as a “0” to the audio system. However, if it hits a smooth stripe, the beam reflects into the sensor, which notes that position as a “1”. By accumulating massive quantities of “1”s and “0”s, a digital-to-analog converter can reconstruct this digital signal into an analog one that can be used by speakers to create music .
The Digital Future
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