Vinyl just sounds better, doesn’t it? It’s as if all the scratches and tiny imperfections in the recording work to make the sound perfect.
But how exactly does it work? How do you get sound from a piece of grooved plastic? Well, let’s start with this image tweeted by Vinyl Loop.
That huge spike you see in the picture is the player’s needle, magnified 1000 times. The groves are analog representations of sound vibrations, etched into the record. As the table turns, the needle follows the grove and moves on two axis — up and down, left and right.
The needle’s arm is attatched either to a piezoelectrical crystal or a series of small magnets placed near a coil. The arm moves the two magnets relative to the coil, generating small electrical currents which are picked up, amplified, and turned into sound — Andrei covered this in more detail here. The scratch sounds you sometimes hear on a vynil are either particles of dust cought in the grove — that needle up there is only about 1-2 mm thick — or actual scratches on the grove.
And now, through the wonder of modern technology, you can see how vynil stores sound in this video Applied Science put together of a record under the electron microscope. It’s a really nice video, but skip to ~4:25 if you’re only interested in seeing the groovy action. Enjoy!