Here is some brief and helpful information about how a vinyl is made.
The music/sound is converted to analogue signals which vibrate a diamond cutting stylus.
A lathe is used which cuts a groove from (left and right– to produce stereo) and ( up and down for the -bass and treble) this is cut into a polished 14″ aluminum disk which is covered with a plastic coating.The machine is referred to as ‘The Curtain Coater’. This plastic coating is called Nitro cellulose Lacquer (the Lacquer)A similar substance to nail polish.
Polished Aluminum disc ready for the lacquer
The center spindle hole is punched out by a hydraulic puncher machine.
Each lacquered disc is inspected manually for any imperfections it is reported that at least 50% are rejected and recycled.
Lacquered disc ready for mastering
The Cutting of the disc would be done in the studio on a lathe by the engineer.
THE ENGINEER would adjust the EQ and compression to get good clean sounding grooves.
Theplayingtime of the music, determines the amount of grooves per inch that would be cut in to te record.
The sound dynamics of the music determines how far apart the grooves must be.
: Loud passages need more space between the grooves than quieter passages. The cutting machine (lathe) would automatically adjust these grooves accordingly depending on the amount of signal frequency that is being received. After all grooves are checked we proceed to make metal copies from the master.
Photo of the sapphire tipped cutting Lathe.
A Lacquer is sprayed with a silver solution (to make it into a good conductor of electricity) it is then placed into a bath containing a nickel sulphamate solution, Photo of the sapphire tipped cutting Lathe.
Then an electric current is passed though this and small nickel particles are attracted to the surface of the lacquer . This is the (+ positive) this then goes into another tank and the process is repeated to produce the mirror image the (-negative) These will be kept as the MASTERS. a further copy is made
THE STAMPERS These thin metal plates are then fitted to a record press -PRESSING – A puck of vinyl material is squashed between two heated moulds under hydraulic pressure, the press puts the labels on at the same time. the 12″ is then trimmed, cooled and packed.
This is the basic process used to make a vinyl record, hopefully this will give you a better understanding when we use such words such as ‘MASTERS’ and ‘STAMPERS’ ‘CODES’ are\were used by manufactures and were stamped or etched on to the run off grooves, often the first pressings were etched with an initial by the master presser.
With a deeper understanding of these manufacturers codes, it can help us to date and understand which master our vinyls were pressed from!
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How Do We Define a First Pressing or Pressed Vinyl Record