How do vinyl records work?
There was a time when everyone understood how vinyl worked. Nearly every household had a turntable (also known as a phonograph or gramophone back in the day when you would hand crank to get your music - thanks, Thomas Edison) and at least a few records, and it was the only way you could listen to music - no digital music means no MP3 files, no compact discs, and certainly no Spotify.
Up until the recent comeback of vinyl albums, however, fewer and fewer people have owned record players or the vinyl discs that go in them. Because of that, many people don’t understand how vinyl records work. The good news is, you don’t have to be an avid record collector just yet to learn about how these nostalgic plastic discs are able to put out our favorite tunes.
In this article, we wanted to address this question and explain the process from creation to the sound you hear, and exactly how vinyl records and turntables work to produce music. We’ll explain every step of the process, including how they’re made, how turntables are produced, how they read vinyl records, and more.
How are vinyl records made?
To understand how you can get music out of a piece of plastic, it’s important to first explain how vinyl records are made. There aren’t a lot of pressers out there at this point, and all of them use a variation of the same method.
Though originally made from shellac, vinyl records are generally made from polyvinyl chloride (PVC), which is the most commonly used synthetic plastic in the world. It’s used for various types of piping, children’s toys, and other consumer products.
This material is made into what are called “biscuits,” which are big chunks of vinyl that can then be cut into the proper shape.
Before they can press the vinyl records, though, they have to first create a master. This is a disc made of some kind of metal, typically, and the sound waves and sound vibrations (thus the sound recording) of a given song or album are imprinted onto this disc.
They then use this metal master disc to press the grooves into vinyl records that get shipped out to you.
But knowing this doesn’t answer the question of how music comes out of record grooves on a flat disc of lacquer. To answer that, we have to explain what sound waves are and how they work.
What are sound waves?
Every sound that you hear comes at a specific “wavelength.” As sound travels through the air, it vibrates at a specific frequency, which creates the sound you hear. When your eardrums detect these vibrations, they send it to your brain and turn it into a distinguishable sound.
The sound you hear is just vibrations in the air created by whatever the sound is coming from. In the case of music, the sounds are also at a given pitch or frequency, which creates the notes that we’re used to hearing.
When vinyl records are made, what happens is that the sound waves created by the music are pressed into the plastic, creating a sort of “fingerprint” for the music. You can think of it as a map to the vibrations of the track.
But if you were to just run your fingers along the surface of a record, you aren’t going to be able to hear music. There’s another important piece to this: the turntable.
How does a turntable work?
There are a few elements to a turntable that allow it to turn the musical fingerprint of a vinyl record into Pink Floyd’s Dark Side of the Moon at max volume. These include the rotation of the table itself, the stylus, an amplifier, and speakers.
The Turntable
The turntable is made up of a couple of moving parts. The first of these is the part that turns, also called the platter.
This is the part of the table that you place the record onto. It usually has a center spindle that you place the hole in the center of the record on to keep it still and some sort of anti-static mat. These can be rubber, cork, or other material.
The second piece is what makes the platter turn. This can vary based on the table in question, but it will usually be either a direct drive or belt drive motor. Belt drive turntables are more popular, but they have their drawbacks.
With a belt-drive, you get less torque than you do with a direct drive motor. Also, belts are likely to wear down over time and need replacing more often than with a direct drive motor.
Whichever style you have, the motor is what causes the platter to turn at a specified speed. This is vital to record playback, and the imprints on the disk will only sound right when played back at a specified speed. If you change the speed, it can change the frequency of the track.
This is why if you’ve ever sped or slowed a record down, you hear the track go higher-pitched or lower-pitched, respectively. Most turntables have a slider that will let you do this, but you’ll need to stick with the intended speed to get the experience the artist intended.
Most LPs are cut at 33 ⅓ RPM, but that isn’t always the case. Many singles are cut at 45, and some older records are as high as 78. The majority of modern record players can play at any of these different speeds, fortunately.
The Stylus
In addition to the spinning turntable, you also need something that can read the music on the disc. This is what’s called a stylus. Attached to the stylus are two other pieces, as well: the tonearm/cantilever and the cartridge.
The tonearm helps to keep the stylus touching the surface lightly, without too much pressure. It is counterbalanced to prevent the stylus from scratching the surface of the vinyl or otherwise causing damage.
It also allows the signal picked up by the stylus to be transferred out of the turntable to the amplifier, but we’ll get back to that.
The stylus itself is made of some kind of crystal, typically either sapphire or diamond, that vibrates as it reads the information on the disc. Those vibrations are read by the cartridge, which turns those into an electrical signal that can be sent out.
Interestingly, the only thing required to make a sound is the turntable itself. If you hold your ears down next to the stylus as the record turns, you can hear the song exactly as it sounds plugged through the speakers. The only difference is the low frequency, i.e. the volume.
It is incredibly quiet without some form of amplification, which is why we also need a few more pieces. A preamp, amplifier, and speaker are necessary to get something listenable out of the record.
The Preamp
Preamps are necessary to get a listenable signal out of your vinyl records. Some turntables have these built-in, but in other cases, you’ll need to purchase an external one. To explain the need for this, we need to talk about phono and line signals.
When sound comes out of a typical turntable, it is sent as a phono signal. Simply put, a phono signal is extremely weak, at around 1-10mV. For context, a speaker typically requires closer to 10-30 volts of power, which is significantly more.
To get the signal from the turntable strong enough to drive your speakers, you need to amplify it. That’s where a preamp comes in.
It takes the phono signal, beefs it up, and turns it into a line signal that can be read by an amplifier. It will also correct the tone of the signal, as the record will usually have trebles boosted and bass lower to save space on the vinyl.
The Amplifier
From there, the preamp will send the signal to a power amplifier, which just amps up the signal even more. You can use a setup without an amplifier in some cases, but it depends on whether you have active speakers or not.
Many amplifiers have built-in preamps, too, but not always. You will often need both pieces.
The Speakers
Last but not least in the audio chain is the speakers. If you have active speakers (sometimes called powered speakers) you can skip the amplification, as those have that built-in.
That’s a less expensive way to build a vinyl setup, but you will usually have lower sound quality with active speakers. To get the real audiophile experience, parting out your setup is usually best.
Once you run the amplifier to your speakers, you’re good to go! The sound travels from information on the record, through the stylus into the cartridge, up the tonearm, through the preamp, amp, and finally into the speakers so you can hear your music.
Remarkably, this technology hasn’t changed much since the early 20th-century. The amount of moving parts it takes to get information embedded in plastic through speakers and into our ears is an incredible innovation in technology.
Sure, you can stream music any time you want now on your phone in the era of digital recording, but there’s something special about firing up a long-sought-for vinyl record for the first time and hearing the warmth and sound quality that only comes from vinyl.
If you’re looking to add to your vinyl collection, check out our curated text offers at Sound of Vinyl. We ask you a few questions about the music you like, and then we send you records we think you’ll love every day. It’s free to sign up, and if you see a record you like, all you have to do is reply.
We’ll ship the record right to your door so you can throw it on your turntable ASAP. If there’s a specific album you’re looking for, browse our collection of rare and limited-edition vinyl records. We’re sure you’ll find something you’ll love.
Sources:
http://www.americaslibrary.gov/aa/edison/aa_edison_phonograph_1.html#:~:text=Thomas%20Edison%20created%20many%20inventions,recording%20and%20one%20for%20playback
https://www.recordplayerpro.com/anatomy-of-a-turntable-a-beginners-guide/
https://www.turntablelab.com/pages/recording-vinyl-into-your-computer-guide