Vinyl history, metal parts: stampers

After a decade of writing about vinyl, and in passing, the minutae of it’s manufacture as a route to determining provenance, I admit I had never actually seen the metal part that actually created the final grooves in the vinyl that we play: the stamper.  At least not until now. So a post that will mean nothing to most people. History may look back on this moment with different eyes.

Larry The Plastylite Guy stumbled on some stampers being sold on a certain auction site. I am not sure why anyone would be in the market for stampers – it’s not like you could use them to press records you wouldn’t want anyway, however they are a fascinating artefact, to some of us at least.

The haul was delivered to Larry. A batch, seemingly dating back to 1975, not of any records of note, but forty five years old, and the real thing.Larry made me an offer, in the best spirit of American generosity, would I like one? Would I heck!

FedEx swings into action, stampers move through cargo handling, and eventually, in another country, far far away. . . and some time later . . . arrive! Larry did a good job packing, bubble wrap, packing tape, protective plywood sheets, it took nearly five minutes to extract them.

Record stamper envelope

Out of the box, the silent witness,  a filing/record-keeping envelope for a stamper designed to keep  track of usage of its use. Stamper library functions: In Date Out Date, process control markers, Press Number, Set Up Man, Mono Stereo, and the most important numbers of all – the number pressed with that stamper in that session. It is blank, but what a story a card like this card could tell.


Something similar must have existed at Plastylite: Van Gelder metal, filing jacket, the running total of number of pressings made with that stamper, the dates of those pressing runs – in the original issue run, subsequent additional pressing sessions. Two years later the same stamper goes to work again. No-one needed to know this except Plastylite.

If you had this record filing card for the stamper of every Blue Note title, you would know the detailed pressing history of everything. Launch issue,  4,000 copies pressed of this title, 2,000 of that title, an extra run of a 1,000  to keep up with sales, actual dates. Collectors worship at your feet. But we don’t have them. The use of Van Gelder metal ceased with the handover by United Artists to EMI. These jackets and their precious metal cargo tossed as unnecessary use of storage space, I could weep.

The Stamper

Inside the envelope, this little beauty emerged into the daylight, surprisingly light and thin, just under 160 grams. A curved edge with marks where they have been fitted into a press. The large centre hole awaits central pressing die, around whose rim the groove is defined.

Engravings, matrix codes, Van Gelder Stamp (if present, which it isn’t) on the run-off  groove area , reversed and transposed right to left. I think I can spot a deep groove in the making. Turn it over, hollowed-out back.

The back of the stamper shows rough finishing marks, and the interval between the tracks on the pressing side can be seen.

Larry kindly sent two stampers on holiday to London. The second stamper is quite different: unlike the curved profile Stamper 1, Stamper No.2 is entirely steam-rollered, pancake  flat.

And that’s it. Stampers are done.  In an odd turn of events, the filing card envelope turns out to be the most iinteresting discovery, if the least attractive.

For collectors of music history, the prized item is actually the acetate rather than the down-stream derivative metal parts. In theory it can be played. A London store was offering these acetates of ’70s prog-rock, as collectable items. Want to be the only person in the world with something? For a price, you can be.

“Closely supervised viewing only”. Somebody bought them not long after put on display. People want a piece of history, not an infinitely reproducible copy.

I can relate to that, good for them, preserving history, times that will never be repeated.




5 thoughts on “Vinyl history, metal parts: stampers

  1. Fascinating glimpse at how records are produced. My understanding of the process is the original wax or acetate is cut and then plated to produce a metal 1st Master with raised grooves. However this is not used to press records as if it was damaged or became worn out it would mean returning to cutting again from the master tape. The intermediate stage are Matrices or Mothers, plated metal discs are produced from the Master with grooves reversed to their usual position. These are then used to produce the Stampers, again with raises grooves to press the discs. So there are three separate stages in production to produce sets of Stampers to produce the finished vinyl discs.
    Found this out many years ago from my grandad who was a record presser, thought this would be a good page to add this info which isn’t always generally know.


  2. Hello London Jazz Collector,
    Here in Long Island New York, back in 1972-73, I worked at a record pressing plant for a small record company, called “Crest Records.” This was a label that predominantly recorded school concerts, mostly high school spring concerts, choirs, etc.; pressing limited editions of course, only for a specific high school, for students and their parents to buy.
    The company also had its own label. with a small roster of classical artists, and a few jazz and rock artists as well, almost all of these artists being unknowns who were not household names. Crest records has a website if you want to look them up further.
    Their main revenue came from pressing major labels’ releases which were overloaded by volume, a prime example being The Rolling Stones U.S.A. anthology on London Records, “Hot Rocks.”
    Anyway, I was employed there sleeving finished new LPs, for about 9 months or so. We pressed and sleeved copies of Hot Rocks for several weeks or more;, from late 1971 into 1972. I think when the metal stampers had done more than they were gauged to do, they were simply thrown out. I was permitted to take one used stamper for one side of the Stones’ Hot Rocks release as a souvenir. I still have it of course, and when I show it to people, I always have to explain why it cannot be played on a record player. It figures, doesn’t it.
    Edward Fenning


  3. Andrew,
    Thanx for your kind words. Our stampers at Plastylite were like the larger, ‘outer-rimmed’ example. I tend to think ours were a bit heavier (thicker.) The rear was sanded with emery cloth, cleaned, wiped and blown with compressed air prior to fitting into the press to (hopefully) prevent ‘dents’. That center rim is the part that would separate from the rest of the stamper- requiring a different center die to secure the stamper in the press (giving the ‘deep groove’???) When we pressers received a set of stampers they were in a sleeve/jacket, but I don’t recall them looking like the ones you (now) have…just ‘blank’, without any spaces for pressing info…could be wrong here…some 55 years ago…I never did research the stamper numbers to see what the recordings actually were.


  4. Unlikely they were “tossed”, I believe that unless claimed by the label after a certain time old stampers are scrapped/recycled, they may not weigh much, but several thousand do and they also take up space, most labels/artists had no interest in the metal parts. As for acetates, although they are made the same way, there is a difference between promo/listening copies as in the Apple acetates above and those destined for plating, you don’t get nice company labels on manufacturing acetates. Once upon a time every studio or label of any size would cut acetates as listening and promo copies, even into the eighties a label like CBS would cut an acetate copy with custom label and even custom sleeve rather than run off a cassette, limited runs of exclusive mixes were also cut as promos, perhaps they still are. All this talk of acetates made me check Popsike for Blue Note and there is a single period LP one for Lou Donaldson BLP 5030, I would assume there would be at least one reference copy for every LP or session including unreleased sessions and Rudy may have cut several with the label, artist and even reviewers/deejays getting one, but perhaps not considering the lack of sales, perhaps shelves of acetates were skipped when Blue Note moved west or maybe they are in storage at Iron Mountain, I was very surprised to see just one.


    • Hello Dubmart,
      I used “thrown out” casually but you are right. I do seem to remember them being recycled at the plant. Thank you for your comments, clarifying further what I did not include in my earlier post!


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