SH Spotlight A quick primer on how records are made

This will go into the FAQ soon...

Records have been made the same way since 1900. Something is recorded on a revolving wax or acetate disc by sound vibrations of a sharp stylus. Pre 1925 the sound was "fed" to the revolving disc acoustically via a big horn with the stylus on the end. After 1925 and the invention of the electronic MICROPHONE, these "electronically recorded" records were cut the same way. By 1951, most performances were not done LIVE anymore onto disc but instead TAPED for cutting at a later date.

No matter the method, the actual cutting has remained the same since 1900. The sound vibrations are cut into a soft record or lacquer.

The lacquer is then "sputtered" with pure silver to make it conduct electricity.

This silvered lacquer is then put into a bath where a nickel layer is slowly built up over a day or two. This nickel is then peeled off and is called THE METAL MASTER. Now this metal master has mountains instead of a groove ('cause it's the opposite of the lacquer it was built up from, like a plaster of Paris mold). So, in order to HEAR the results------

The METAL MASTER is again put in a nickel bath and a new layer is built up. When it is peeled off it now has grooves again instead of mountains and it can be played on a turntable to hear what it sounds like. This new part is called the METAL MOTHER.

If it sounds good the METAL MOTHER is ready to be used in the final metal step before pressing a record.

The METAL MOTHER is put in the bath and a new nickel layer is built up on it that will once again have mountains instead of grooves. When this is peeled off it's called THE METAL STAMPER.

When the METAL STAMPER is ready for both sides of the album, the TWO METAL STAMPERS are put on the pressing machine with one above and one below the press and a warm vinyl biscuit is inserted between the top and bottom stampers. The machine comes down like a waffle iron and presses the records from the METAL STAMPERS.

When the STAMPERS start to wear out after about 500 or so pressings, NEW STAMPERS have to be made from the METAL MOTHERS. When the METAL MOTHERS start to wear out, NEW METAL MOTHERS are made from the original METAL MASTERS. When the METAL MASTERS start to wear out NEW LACQUERS HAVE TO BE RECUT. These "replacement" lacquers are usually called RECUTS and can be done weeks, months, years or even DECADES after the album was first released. Sometimes the record company will cheap out and only recut one side, using the original A or B side of a 20 year old metal part for the other side. This results in one side being of a different fidelity than the other side. Drives us record collectors crazy.

At any rate, the METAL MOTHER can be played on a turntable and in the days before tape (the 78 RPM era) this is how music was preserved for future generations. MOTHERS exist from the tape era as well and they sure can come in handy if the original master tape is lost or damaged.

So this is pretty much how they have been doing since your Great, Great, Great, Great Grandfather's day. It still works remarkably well, don't you think?

Here is a picture of two of the process. Scroll down on these threads:

http://www.stevehoffman.tv/forums/showthread.php?t=7372


http://www.stevehoffman.tv/forums/showthread.php?t=398
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SH

 

Jamie,

Cutting genius Stan Ricker can explain better than I can! Here he is from a Positive Feedback interview from a few years ago...
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Dave Glackin:

"What's your opinion of the dehorning of masters?"


Stan Ricker:

"Well, I don't know of anybody who does that anymore. It seems to have been fairly popular in the sixties or seventies or whenever. A cutter stylus cuts and it also plows. With a snow plow you go down the road and you pile up all this humongous crap along the curbs and sidewalks. Well, you hope you don't get much of that when you cut. Cutter styluses are manufactured much better nowadays than, shall we say, thirty years ago. The burnishing facets weren't so accurate then. Sometimes you got a nice cut in the groove but then sometimes you didn’t, and there might be a bunch of stuff stacked up at the edge of the groove. That stuff was rough-textured and made separation of the lacquer master from the first metal plating very difficult, because the stuff that's thrown off, when viewed under a microscope, looks like a string of cinders. It's porous, like a sponge, you see. So when you're electroplating that stuff, well, the metal molecules get inside and you can imagine metallic nickel getting inside a sponge and then how do you peel a sponge off that electroplating? You're left with little bits of stuff stuck to the metal (NOISY!). So the idea was to knock off those. It affects the sound. I don't know anybody who does dehorning anymore. At least I don't know anybody that's involved in high quality work who does it, mostly because there’s no need for it with today’s better styli."

 

Robert,

The second approved cutting lacquer.

 

Here's another take on the cutting and manufacturing process:

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The following excerpt is courtesy of the Interstate DJ School DJ Training Curriculum, written and assembled by Robert Oleysyck

How Vinyl Records Are Manufactured
by Robert Oleysyck, Interstate DJ School, Las Vegas, Nevada


Starting with a master tape, DAT, or CD, the music is transferred to an aluminum disc covered with lacquer, which is done using a "cutting lathe," Hence, the term "cutting a record." With a slightly heated sapphire or diamond tipped stylus, the lathe etches a spiral groove into the soft, oil based lacquer that starts from the outer edge going in. The stylus has two coils (one for each left and right amp channel) that are positioned between magnets. The music master is fed into the magnets, varying the magnetism, which in turn causes the stylus to vibrate left and right. The stylus can oscillate at up to 16,000 times per second. The greater the volume of the material, the wider the groove.

This process is almost the exact reverse of playing a record in the usual manner using a turntable, normal stylus, and cartridge. Each lacquer disc is single sided so two must be produced for a regular two-sided record. Cutting is the last stage at which the sound can be altered (and only to a limited extent). To ensure a consistent, distortion-free transfer of the signal to the blank disc, great care must be taken not to cut too deep, shallow, loud or quiet. If the cut is too deep, the playback needle may not sit snugly in the groove or reach the bottom; if it is too shallow, the needle may skip tracks.

There is a trade off between recording level and duration per side. Cutting at 45 RPM offers a higher resolution, meaning that the sound is spread over a longer length of the groove, with more space between grooves as opposed to a 33-RPM recording. That's why a 12" single - with one track on one side - will sound far better than an LP with 5 tracks on one side.

In the next stage, the lacquer disk (in some cases referred to as an acetate) is put through a process called Galvanic Electro Formation. Through special cleaners and agents, a metal layer of nickel and silver is formed over the lacquer, creating a metal plate. This new plate is a negative of the previous master, having ridges instead of grooves, from which, several successive metal parts are produced:

The "Mother" is a positive plate identical to the finished record that can be played and looks like the gold discs awarded for sales.

The "Stamper" (one for each side) is also a negative, and is then used to stamp out or press the records. The stampers are used to "press" the grooves into preheated polyvinyl thermoplastic discs, otherwise known as records. With the aid of a stabilizer and lubricants, the vinyl is fed to the press and formed into a "puck" or "biscuit." With the labels on their appropriate sides, the press closes, and the stampers squash down on the biscuit to form a record. After being cooled by water, the record is trimmed and left flat to cool. Test pressings are usually made to check the quality of the sound and for any flaws, which may occur.

 

Most stuff today is cut from digital. Heck, Martin, most studios can't even cut from an analog tape at all because the "preview" head is now a digital delay.

Of course, the studios I work in CAN still cut from analog...

 

I guess it worked for the latest set of Doors' LP's. They got rave reviews..