- Mastering for vinyl
- Making the master disc
- Making the stamper
- Biscuit, anyone?
- How are the labels attached?
- Pressing the records
- Test pressings
- Production and beyond
- How vinyl records are made – conclusion
In a factory. There, that was a short article.
Wait, come back! Let me tell you how vinyl records are made. After all, if you’re reading this, you’ll have been wondering just how the music gets on those big, round plastic things you put on your turntable.
The process is still largely the same as it was decades ago, although with some additions and improvements to the technology used.
Let’s look at the various stages in turn.
Mastering for vinyl
After musicians have bought instruments, learned how to play them and written and recorded some songs, which somebody has then agreed to release, the music is sent for mastering.
Unmastered tracks are too quiet, and are still lacking the polish required to make them sound as good as other commercial releases.
Tracks used to be sent for mastering on 1/4″ (about 6.35mm) tape, but people now work with digital AIFF or WAV files.
In an ideal world, there would be separate masters for vinyl, CD and the streaming/download versions of a release, with each master taking into account the idiosyncrasies of the intended format’s dynamic range. But in the real, non-ideal world, vinyl is sometimes mastered from the CD master. Grrr…
Preparing for a vinyl release
Before the mastering engineer can begin their actual mastering work, there are a number of things that need to be cleared up.
First of all, when reparing a release for vinyl, the running order of the tracks has to be considered very carefully.
On the one hand, to ensure that the side split occurs in a logical place and that each side of the record can hold the amount of music assigned to it.
Another factor that must be considered is to ensure the most dynamic tracks appear at the start of a side. Ever noticed how many of your favourite albums feature the best tracks at the beginning of sides 1 and 2? This is because the sound quality is best at the beginning.
Why’s that? A groove runs along each side of the round record, starting from the edge and working towards the centre. The groove circumference is therefore greater at the edge (the beginning) than it is near the centre (the end). As the groove gets shorter per second of music, the music’s resolution becomes lower. This is like gradually reducing the resolution of a digital file as it plays. Imagine that!
Hmm: I wonder if that’s why the tracks on live albums are sometimes in a different order to how they were played at the concert? (Apart from them also having to fit on their respective sides.)
How is mastering for vinyl different to mastering for other formats?
Vinyl reproduces a narrower frequency range than digital formats. If the music contains too much activity in the high end or low end, or too much distortion, this causes the record to skip and jump.
For the same reason, if the engineer makes the music too loud, the sound will be distorted, also causing the record to skip.
And the higher the amplitude, the wider the record’s grooves need to be, which in turn reduces playing time.
The mastering engineer has to give such technical questions proper consideration.
What does mastering for vinyl involve?
Once all these matters have been considered and cleared up satisfactorily, the mastering engineer then does a number of things, such as applying and fine-tuning EQ and limiters, plus tweaking the stereo image. They also ensure that all tracks have a uniform perceived loudness. This is all based on their knowledge and experience of how sound in general and this collection of music in particular will transfer to vinyl, which in turn requires a deep understanding of frequencies and dynamics.
There are no ‘one size fits all’ settings, although engineers typically have a set of templates to use as starting points.
Making the master disc
After mastering, the next stage in the process of making a vinyl record is to create the master disc.
This involves transferring the music in the digital file to an aluminium plate covered with a thick coat of lacquer.
Some mastering engineers are able to do this themselves, whereas others send the files to a specialist cutting engineer.
The master disc is created by a lathe (lathe cutting). Imagine a piece of equipment that looks a bit like a record player. A sapphire stylus on the machine’s arm turns the music’s sound waves (electrical signals) into vibrations, cutting them into the plate in the form of a groove, creating the master disc.
During this process, the master disc gets so hot that it is continuously cooled with helium!
A master disc is created for each side of the record.
This occurs in real time, with the gaps in between the tracks being manually created by the cutting engineer moving the stylus a bit further towards the centre as the master disc is rotating.
Although lacquer masters are used as standard, there is also another, albeit rarer, procedure: direct metal mastering (DMM). In this case, a lathe with a diamond stylus (not sapphire) cuts the grooves directly into a copper master disc. This results in better sound quality, but the technology emerged in the 1980s, just as CDs appeared and gradually became the default way for people to buy and listen to music.
As a result, it never became widespread, and today there are only a handful of plants in the world that are able to make vinyl records using this procedure. The last remaining DMM machinery in the USA was sold to the Church of Scientology (!).
And on a side note, I can remember that the Music for Nations metal label used DMM for some of its 1980s pressings. Metal for metal!
Making the stamper
The finished master discs, one for each side, are now sent to the pressing plant, where the next step is to make the stamper.
First of all, the master disc is carefully washed, to ensure it is free of dust and other contaminants, and sprayed with liquid silver.
It is then placed in a nickel bath for electroplating (also called electroforming). A nitrate is applied to the lacquer, which attracts nickel, so that it fills the grooves.
This electroplated master is then pulled apart, which results in two discs that are a mirror image of each other. One has grooves (actually, one continuous, circular groove!). This is the original lacquer master, but isn’t used for pressing records.
The other, the negative, has raised ridges, and is called the father (or metal master).
What happens next depends on how many copies of the record are being pressed. It’s necessary to strike a balance between quality and quantity, as no matter how the stampers are made, they eventually wear out. But: the more stages there are in the procedure, the greater the chance of contamination creeping in somewhere.
The 3-stage process
For larger pressings, for example, all those 1980s Phil Collins albums cluttering up the country’s charity shops and car boot sales, the three-stage process is necessary.
In this process, the father is electroplated as described above and is split apart again, creating the mother. This is therefore a negative copy, usually made from copper, which means it is stronger than the father. And as it has grooves, not ridges, it is playable. Indeed, it will typically be played, to ensure that the process so far has worked as expected, and that there are no unpleasant audio surprises.
In turn, the mother is then also electroplated, to create a negative copy of it, with ridges, not grooves. This copy is the actual stamper used for pressing the records.
The 2-stage process
For smaller pressing runs, the father is split as previously described, and this is then directly used as the stamper, ie without creating a mother and creating the stamper from that.
Although this process is easier and therefore cheaper for smaller runs, it could be described as cutting corners. If demand for the record increases and many more copies need to be pressed, once the mother wears out, there is no father from which to make another. This means a new lacquer master has to be created.
Let the stamping begin!
Whichever process is chosen, the records can now be pressed. (Stamping now for stomping later – depending what music’s on them, of course!)
The video below comes from one of Europe’s largest pressing plants, Record Industry in the Netherlands, and shows the vinyl manufacturing process from making the stamper to the finished records landing in their sleeves.
How long do all these components last?
Regardless which procedure was used to make them, the stampers gradually wear out, meaning that the audio quality degrades. Each stamper can generally produce around 1000 records, meaning that several will be needed for larger runs. Once a stamper has worn out, the father or mother has to be electroplated and split again.
But the mothers and fathers also wear out. (Any worn-out mothers and fathers reading this will probably know what I mean.)
A father can produce about 10 mothers, and a mother can produce about 10 stampers. Depending on the process used to create these bits and pieces, after about 10,000 or 100,000 (!) records, a new master disc will have to be made.
The vinyl spinning around on your turntable started its life as polyvinyl chloride (PVC) pellets.
These are loaded into a hopper on the press, where they’re fed through an extruder and melted and squashed to form what are called biscuits. As the name suggests, these are round, flat discs – although not as flat as they will be when they’ve been pressed into records!
Are the vinyl pellets always new, or are they made from rejects that have been ground down? ‘Virgin vinyl’ is sometimes used as a selling point, but the pellets are generally a mixture of old and ground down pellets, with 70 new/30 used being a common ratio.
Biscuits are made to different weights, so when you see a record being advertised as being on 180 gram vinyl, this is what it means.
The following video, again from Record Industry, shows a delivery of pellets being turned into biscuits, and ultimately, vinyl records.
How are the labels attached?
By this stage, the labels have already been printed and afterwards baked in a special oven to dry them out and prevent bubbles occurring.
Perhaps contrary to what you may think, the labels aren’t glued to the records. The pressure the records are pressed at causes them to bond to the polyvinyl chloride of their own accord! They’re ‘baked in’ to the records.
Pressing the records
The biscuits and labels are ready.
The next job is to fit the stampers into a hydraulic press, so the records can actually be pressed.
This is a bit like one of those sandwich toasting machines.
At the bottom of the pile is a stamper. On top of that there’s the label for that side, facing down. Then the biscuit. And on top of that, the other label, facing upwards. Finally, the other stamper is at the very top.
Once all these elements are in place, the biscuit is steam-heated to 148°C (300°F) and about 100 tonnes of pressure are applied to the hot vinyl material. The grooves are pressed into the record, and the labels bond with the material as described above.
After the records have been stamped, the pressing machine trims and rounds their edges and cools them with water, before they land on a spindle, with the whole process only taking about 30 seconds. New biscuits and labels are continuously fed into the machine, making the manufacture of vinyl records a continuous process.
Even at this stage, it’s still not time for thousands of copies of the latest eagerly awaited big seller to roll off the presses.
First of all come the test pressings. These are small batches of records – enough copies for artists and labels to review.
Because vinyl inherently sounds different to digital music, the test pressings will sound different to what artists and everyone involved has heard up until now. They therefore represent insiders’ final chance to notice any actual problems, over and above the expected typical surface noise and crackles. If there any massive pops, or problems with the record jumping and skipping, the whole process has to start again, right from the very beginning! (This does occasionally happen!)
Once the test pressings have been approved, the go-ahead for full production is granted.
Test pressings have always escaped into the collector’s market, usually in plain paper inner sleeves or a die-cut ‘disco bag’, but occasionally also with proof sleeves. But since the turn of the millennium or so, as artists’ income from selling recorded music has decreased, some have sold their test pressings via their websites. These are often signed, or with hand-drawn covers or customised in some other way. For artists who have enough of a cult following of people with deep enough purses or wallets, these can represent a useful source of income, as they can command premium prices.
Production and beyond
We’re now nearly there. The records are rolling off the press and landing on waiting spindles. As all this happens, copies may be pulled on a random basis, for closer visual and audio inspection. Some of these will be rejected, which is presumably why pressing plants generally advise that the quantity you receive will fall within a tolerance range, and not necessarily the precise quantity you order.
Rejects are reground and mixed with brand new pellets, as mentioned earlier in the article.
The sleeves have already been printed. Some pressing plants also have in-house printing facilities, but others farm the printing out to other companies, including ones who are their competitors as far as pressing vinyl is concerned.
The records are then taken from their spindles and everything is put together. In some plants, this occurs manually, and in others, the process is automated. But however it happens, the result is the same. The records are inserted into inner sleeves and the inner sleeves into sleeves (or jackets, as they’re called in some countries). Any inserts or booklets are also added, before the records are shrinkwrapped (if specified) and any stickers applied.
They are now sent to the distributors, from which they find their way to record shops and ultimately, your home, turntable, ears and hopefully also your memories.
In the video below, you can see how records at Record Industry in the Netherlands are stickered and shrinkwrapped.
How vinyl records are made – conclusion
So that’s how vinyl records are made. It’s a technical process requiring a lot of specialist knowledge, but is in some ways also something of an art form.
Nowadays we’re used to being able to conveniently listen to the music we love on the bus, in bed or in the bath. But in decades gone by, artists had no choice other than to press their music onto these bits of plastic, with all the problems that can bring – both in the production stage and for the listener at home.
Main photo: Andres Valdes/Unsplash. Videos: Record Industry BV via YouTube. Other photo © musicstuff.info