How Do Vinyl Records Work?
Vinyl records store music and audio in a physical format that can be played back and enjoyed with special equipment. The main equipment being a record player (or turntable), audio cables, and speakers. Most people know this much about vinyl records. You put the record on the turntable, it spins, you place the stylus on the record and it plays through the speakers. While this is all true it’s an overly simple explanation for how a vinyl record really works and is missing some key details.
To get a better understanding of how a vinyl record works we need to dig into the details that are missing from the above explanation. The key details relate to the vinyl record itself and the player / stylus. First we’ll look at the vinyl record itself. You’ve probably noticed that vinyls have a groove that the stylus follows from the outside of the record to the inside when playing. That groove is basically a three dimensional line that was drawn (or cut) by a cutting needle on a metal disc during the recording process. The vinyl that you play on your turntable was pressed with the original metal disc as a copy. When you play your record, your stylus moves through the groove which is a copy of the original cut recording.
As mentioned, the groove is basically a three dimensional line. If we were to zoom in and follow the stylus along the groove we’d see that the groove has a number of modulations. It contains minor twists turns that move the stylus slightly left and right. It also contains hills and bumps, that move the stylus up and down. The left and right modulations are one channel of audio, while the up and down are the other channel. Together they make up a stereo signal. As you might have guessed, a mono recording would only require one type of modulation. For example, just left and right movement.
When the stylus travels through the groove it registers all these modulation details about the groove along the way. When it moves around a slight turn or up over a bump it is actually moving a small device in the tone arm as well, (a transducer) coils in a magnetic field. As the record turns and the stylus traces the groove, all the modulations are registered by the magnetic field. The movements in the magnetic field creates an electrical current. This electrical current is then sent through an amplifier and then to your speakers. The speakers interpret the electrical current and then move, which recreates the sound originally recorded on the vinyl!