From: Patent Tactics, George Brock-Nannestad
Hello,
Mike Biel kindly wrote (by now quite some time ago):
> I am eager to hear from my friend George Brock-Nannestad about this
> discussion since he had done a lot of study of the technical
> documentation in Europe in probably every language. Is he on vacation,
> or pouring thru a basement full of books and photocopies trying to
> research the facts before answering?
----- well, I am back. However, I do find that my primary sources take turns
when disappearing from view. I do not apologize for the long post: skip it if
you are tired of people like me, Mike Biel or other grumblers.
SONS OR STAMPERS
The matter concerned the naming of the metal parts used first in mechanical
record manufacture and latterly in CD and DVD manufacture.
In the main I agree with Mike; the "family" business is predominantly
European, not to say German. I have looked at a few older references (Göran
Finnberg having dealt with the newer), and I think that the oldest general
discussion of record manufacture in book form, Henry Seymour's "The
Reproduction of Sound", Tattersall, London (1918; year from leaflet), has
some very important words to us all:
p. 182: 'The obverse impressions of the original matrix are called "mothers"
in the trade, in view of their office in reproducing matrices from the
"master".'
There is no word about "father", nor "son"; the tool parts are called
"stampers" or "working matrices". It would seem that Seymour and the trade
are very logical; there never was any 'father' or 'son' function as such, but
the 'mother' indeed reproduces.
The word "Sohn" in German is very much older than Fritz Bergtold's book (1954
and 1959); I have found it in Eugen Nesper's "Die Schallplatte", Radio-Verlag
Walter Hillger, Berlin 1930, but I suspect it is much older. After all,
Deutsche Grammophon had the first pressing plant in Europe for non-doll disc
records.
Albert Ebner wrote a booklet in 1923, and he messes everything up: ("Über den
Werdegang des Phonographen und Sprechapparats", Elektromophon-AG, Stuttgart,
1923) p. 35. He calls the cut wax "Mutterplatte", and he jumps straight to
"Matrizen", although he still claims that the "Mutterplatte" remains
available for the generation of more "Matrizen". However, he was a
manufacturer of electric gramophone motors.
In France, there was movement: The standard work in French A. Coeuroy and G.
Clarence, 'Le Phonographe', Éditions Kra, Paris 1929, uses the sequence
'original', 'mère' and 'shell' or 'matrice' (pp. 34-35). However, R. Vellard,
'Le Cinéma Sonore. Théorie et Pratique', Dunod, Paris 1936 uses the terms
'père', 'mère' and 'fils' on p. 153.
VINYL AND INJECTION MOLDING
While I am at it, I would like to put some facts about styrene and vinyl in
perspective. Injection molding is extremely difficult, because the areas are
so large and the flow of material has to reach very far before the mold is
absolutely completely filled. Let me quote from:
Joseph C. Ruda, 'Record Manufacturing: Making the Sound for Everyone', JAES
Vol.25, No. 10/11, pp. 702-711 (October/November 1977) [the 'Indispensable'
JAES issue]
on p. 710:
'Approximately half the 7-inch records produced in the United States and
Europe are molded by the injection molding process. In the United States
these are molded in styrene; Europe's product is vinyl. The first large-scale
production using this method can be traced to installations made in the early
1950s. Many attempts have also been made in the industry to injection-mold 12-
inch audio records, but no practical process has been developed to date'.
The whole paper is a very illuminating description of the state-of-the-art in
1977 as concerns materials and procedures and is highly recommended.
Seeing that the properties, including friction, of styrene compounds (which
would also really be alloys) and vinyl compounds are different, I do not
think we can conclude anything concerning discoloration, noise, etc. without
knowing which material we are talking about when we discuss 7" records. For
10" and above it is all vinyl.
LACQUERS AND ACETATES
There is actually a third pet peeve that I would like to bite into while I am
at it: the ill-famed acetate lacquer surface. I am usually just as haughty as
Mike when "acetates" are mentioned as carriers of sound. However, three
instances have made me slightly wary: chronologically they are an old article
from the film industry, some early catalogues that have been put on the web
(although lawyers will be ambivalent about the more than fuzzy small print
they provide), and a label photo in Lewis Foreman's chapter in the book
"Cambridge Companion to Recorded Music". All the way through he insists on
calling the lacquers "acetates". I protested during the editing and requested
"lacquers", but to no avail.
I have a good collection of the Journal of the Society of Motion Picture
Engineers, laboriously put together and taking up a lot of space. They
contain a fabulous amount of audio information! B.E. Stechbart was an
important moving picture equipment engineer (among other posts he had been
vice-president (engineering) at Bell & Howell), and his privately bound
volumes of JSMPE have been made available from the Prelinger Library on the
Internet Archive, scanned by Microsoft. Recently, Craig Smith of California
has started the laborious process of indexing all the audio material, and he
now covers 1930-32. I hang on to my bound volumes for the time being, because
the pictures are better than those in the scans.
In 1935 we may read a report on the use of instantaneous recordings for on-
the-set playback and re-takes while the actors are in the mood. They used to
have to wait up to a day for the processing of records or had to use wax
recorders in parallel. Also, musical accompaniment was provided by
instantaneous discs. They are consistently called "acetate disk"!! Quote:
"In view of these handicaps, the cellulose acetate disk was brought into use
about a year ago, and at some studios it has completely supplanted all other
methods for obtaining playbacks." (G.M. Best, "Improvements in playback disk
recording", JMSPT August 1935, pp. 109-116).
But the thing that really throws a spanner in the works is provided by scans
of supply house catalogues (Lafayette, Allied) that are available on the
internet [http://reel2reeltexas.com/catIndex.html]. I shall quote:
From: Allied Catalogue 1939, p. 100 (lower part)
Complete Selection of RECORDING DISCS
third section down:
Mirror Acetate Discs (smaller print completely illegible)
[note, up to 16", hence a professional format]
fifth section down:
Federal "Perma-Disk" Discs
New Acetate discs capable of 300 playbacks
when properly cut. Have even coating on heavy
base for greatly reduced surface noise
[note, up to 16", hence a professional format]
[second note: actually, Best in 1935 mentions 300 playbacks !!]
sixth section down:
Federal "Perma-Board" Discs
Acetate-covered composition board disc. Coated
one side only.
[not professional]
tenth section down:
Universal Economy Discs
New lightweight, low-priced acetate
discs ............
From: Lafayette Catalogue 1941, p. 19 (upper part)
RECORDING DISCS
PRESTO RECORDING DISCS. A very popular make
of high quality Acetate discs. Records on both sides.
...........
[note, up to 16", hence a professional format]
From: Lafayette Catalogue 1944, p. 24 (upper part)
RECORDING BLANKS - CARTRIDGES
third section down:
AUDIODISCS
"RED LABEL" Glass Base
Faultlessly coated and carefully selected to the
highest standards of quality. Primarily for
professional use, "Acetate" coated on thin, flex-
ible glass. Double sided with 3 drive pin holes.
For all applications requiring the ultimate in
disc perfection.
fifth section down:
RECORDISC Recording Blanks
The Yellow Label and Green Label Discs listed
below are coated with a slow-burning compound
which is approved by the Underwriters Labora-
tories. For all practical purposes this coating is
substantially equal to Cellulose nitrate coating,
and for home recording is more than adequate.
Shavings are NON-INFLAMMABLE
eighth section down:
Blue Label
These blanks have the same type thermoplastic
base as the Green Label discs, but are coated
with a mirror-like professional cellulose-
nitrate compound. Will record with lower noise
level and greater brilliancy. ....... ...... Shavings
are inflammable.
From the above examples I believe that it is only fair to conclude the
following:
- both "acetate" and cellulose nitrate coats were offered in the trade,
and I do not believe that only the nitrates sold
- the trade was able to distinguish between the qualities of the two, in
terms of noise and inflammability
- we may believe that "acetate" was used for playback lacquers;
whether in broadcasting, I do not know. Probably not, due to noise.
- we will not find many lacquers that have been through processing
for record manufacture, because they perish thereby
- it remains to analyse samples of surviving discs
- possibly, most of the home recordings we find before 1950 are
really acetates
- I think we should hold our fire in future, unless we are very sure.
So, in consequence, I shall have to apologize to Lewis Foreman.
The internet is a marvellous thing, but live libraries suffer. My copies of
the JSMPE are from US libraries.
Kind regards,
George
------------------------------
Mike wrote:
> This is very interesting. I have noticed three things about these
> references and your discussion.
> 1) All of these are relatively recent.
> 2) They tend to be European.
> 3) They are mainly discussing CD replication
>
> CDs are injection moulded, and in this process the discs are not really
> pressed or "stamped", they are moulded when the liquid is injected into
> the already closed press. It could almost be said that calling the
> mould a stamper is incorrect!! Although the same is true with injection
> moulded styrene and vinyl records, because the metal part is the same
> whether it is placed in a compression moulding or injection moulding
> press, during the days of grooved records it was called a stamper in
> either case. (Of course Edison called his cylinder masters "moulds", but
> I don't remember what the Edison disc masters were called -- the
> Diamond Disc manufacturing process was called "printing" not "pressing".
----- Hit-of-the-Week were made in printing machines! (GBN note)
>
> Considering that the older printed sources you referenced to which call
> the part "stamper" are pre-CD, it is possible that the use of "son" came
> about during the CD era when no compression moulding -- or stamping --
> was being done. On the other hand, your personal stories about the
> earlier use of son in Sweden are interesting and they are at the same
> level as my anecdotal experience of hearing only the use of stamper!
> That's why I asked about printed sources since I could provide those
> beyond my anecdotes.
>
> Since the CD was developed by European and Japanese firms, if these
> companies used "son", it probably caught on quicker in Europe. I
> haven't heard American CD replicators using "son", only "stamper", but
> you do show some American sources. However these sources seem to be
> from companies and people which come only from a CD background without
> having prior experience in grooved records. (Remember a month ago when
> we had a reference to a modern California vinyl pressing plant website
> which had a weird description about 78s being made from shellac sheets
> glued to a heavy paper core -- how much do the younger modern "experts"
> know about the history of their industry?)
>
>
> I might mention that the use of the term "father" is also rare -- but
> not unknown -- in my experience, but the term "mother" is almost
> universal!! I have never understood why mother came to be so common
> while father is rare and son was non-existent to me before this
> discussion. The female metal part was given a descriptive female name
> by just about everyone, but why not the male metal parts? And I am
> rather surprised that none of the discussion included the term "shell"
> which was seemingly the official term of the Gramophone Co. to describe
> the metal positive pulled from the original wax. This term is used from
> the very beginning of the company but I don't see it used by Victor, at
> least not as much.
>
> I am eager to hear from my friend George Brock-Nannestad about this
> discussion since he had done a lot of study of the technical
> documentation in Europe in probably every language. Is he on vacation,
> or poring thru a basement full of books and photocopies trying to
> research the facts before answering?
>
> Mike Biel [log in to unmask]
>
>
> ===============
> From: Goran Finnberg <[log in to unmask]>
>
>
> Michael Biel:
>
> > Actually I don't think that anyone has ever heard of it.
>
> > I have read hundreds of books, articles, instruction
> > manuals, guidebooks, etc. about recording techniques
> > and technology dating from all eras of the industry,
> > but have never seen anything relating the stamper to
> > the word "son". Can you cite me some specific sources
> > in print that use this term? I'm not saying that it
> > has never been used, but it must be quite uncommon, at
> > least in English.
>
> I have worked as a consultant to Skandinaviska Grammofon AB in Amal,
> Sweden,
> owned by EMI for most of its life, 1974 to 1989.
>
> It was supposed to be the largest vinyl record pressing plant in Europe
> at
> that time mid 70´s.
>
> All the production people called the parts Father, Mother and Son.
> Including
> calls to EMI England, or when EMI people turned up at the factory in
> Sweden.
>
> Toolex-Alpha once world leader in vinyl pressing equipment called the
> parts
> Father, Mother and Son in the tree day seminar I went to in the 70´s.
> And
> this continued when they began producing presses for CD production when
> I
> helped out some friends who started Logos AB here in Gothenburg which
> was
> once a cassette duplicating plant but later on started producing CD´s.
>
> Sonopress in Germany, and many more too many to list, also referred them
> to
> be Father, Mother and Son.
>
> In fact dealing with hundreds upon hundreds of companies professionally
> involved with mass duplication of Vinyl or CD disks here in Europe I
> have
> always seen, Father, Mother and Son, to be used as description of the
> three
> stages used to provide a replicated LP/CD disk to be used as the final
> carrier to be sold in the retail shop.
>
> Using Google with the keywords:
>
> Record Pressing Father mother son stamper
>
> Turned up several hundred hits to numerous to list here but I looked at
> a
> few:
>
>
> http://www.soundonsound.com/sos/sep03/articles/artwork.htm
>
> The etched glass master is not used to stamp discs itself, but is used
> to
> create a metal stamper through a process called electroforming. A layer
> of
> nickel is effectively grown onto the disc, transferring the etched pits
> on
> the glass into bumps in the metal disc to produce a 'father' disc. For
> very
> short CD pressing runs, this father can be used as the direct stamper,
> but
> it is more common to produce one or more 'mother' discs from the father,
> and
> then several 'sons' from each mother. The sons are used as stampers to
> produce the raw plastic CD discs
>
> -------------------------
>
> http://www.pctechguide.com/32CD-ROM_Manufacturing.htm
>
> In a process known as "electroforming", the metalised glass master has a
> layer of nickel grown onto its silver surface by immersion in a tank of
> nickel sulphamate solution. This sheet of nickel - referred to as the
> "father" - is subsequently removed from the silver. The father is a
> reverse
> image of the data and could be used to stamp discs. However, it is not.
> Instead, the father is returned to the electroforming tank where another
> layer of nickel is grown and subsequently removed to create a "mother".
> The
> mother undergoes the same process to produce a "stamper" (sometimes
> referred
> to as a "son"). Several stampers can be grown from the same mother.
> CD Pit Structure
>
> -------------------------
>
> http://www.freepatentsonline.com/y2009/0232928.html
>
> " Also, a mother stamper or a son stamper may be manufactured from the
> father stamper. "
>
> -------------------------
>
> http://www.faqs.org/patents/app/20090195925
>
> [0106]Further, in the same manner as a procedure of obtaining the mother
> stamper from the father stamper, an oxide film is formed on a surface of
> the
> mother stamper, and an Ni film is electroformed and released, thereby
> obtaining a son stamper having the same patterns of the father stamper.
>
> ---------------------------
>
> http://www.odiscs.com/cd/cd_structures_formed.htm
>
> After the exposed areas are developed away by conventional methods to
> produce pits, a rigid metal negative to the master, called the Father or
> Master stamper, is produced by an electoplating process (see Figure 2).
>
> A multiple positive image Mother may be electroplated from the Father
> stamper. In turn, negative image Son stampers are plated from each
> Mother to
> produce multiple copies of the original master.
>
> Mass replication of the source begins by mounting a Father or Son in a
> molding press. Melted plastic is injected into the cavity and allowed to
> cool. The pits from the stamper are accurately reproduced in a plastic
> substrate, forming the original positive image.
>
> --------------------------
>
> http://www.answers.com/topic/compact-disc
>
> Next, the newly applied metal layer is pulled apart from the disc
> master,
> which is put aside. The metal layer, or father, contains a negative
> impression of the disc master track; in other words, the track on the
> metal
> layer is an exact replica, but in reverse, of the track on the disc
> master.
> * The metal father then undergoes further electroforming to produce one
> or more mothers, which are simply metal layers that again have positive
> impressions of the original disc master track. Using the same
> electroforming
> process, each mother then produces a son (also called a stamper) with a
> negative impression of the track. It is the son that is then used to
> create
> the actual CD.
> * After being separated from the mother, the metal son is rinsed, dried,
> polished and put in a punching machine that cuts out the center hole and
> forms the desired outside diameter.
>
> --------------------------------------
>
> http://www.patentstorm.us/patents/6814897.html
>
> According to a preferred embodiment of the invention, a first metallic
> (Ni)
> mold tool (father) is made which is a duplicate of a master substrate,
> then
> a resin mold tool (mother) is made which is a duplicate of the first
> metallic mold tool and finally a second metallic (Ni) mold tool (son) is
> made which is a duplicate of the resin mold tool. Both the father and
> son
> may be referred to a ³stamper².
>
> ---------------------------------------
>
> As I have also had to deal with Georg Neumann record cutting equipment
> then
> all the descriptions dealing with what happens after the laquer being
> cut
> then the descriptive words Father, Mother, Son was always used.
>
> Nowadays I am helping a young man who have bought an old Neumann VMS66
> cutter here in Gothenburg and he recently added record plating equipment
> to
> his services and without no promting from me he called the process
> Father,
> Mother Son when he spoke about this process as he had learnt it from the
> previous owner.
>
> http://www.tailrecvinyl.com/
>
> So to me at least, this is universally used here in most parts of
> Europe.
>
> But looking in the 1973 edition of the EMI Technical Glossary page M2
> says:
>
> MATRIX:
>
> A metal part, originally produced from a laquer master, by the
> electrodeposition of nickel:
>
> 1. Metal Master (Negative).
> 2. Metal Mother (Positive).
> 3. Metal Stamper (Negative).
>
> It is stated at the very beginning:
>
> The terms used here are the most commonly used in the recording and
> manufacture of gramophone records.
>
> Gilbert Briggs, owner of Wharfedale loudspeakers, England in his book A
> to Z
> in audio, 11/1960 states on page 166:
>
> The sequence of record processing is as follows:
>
> 1.Laquer original - positive.
> 2 Metal Master - negative.
> 3 Metal Mother - positive.
> 4 Metal stamper, known as the working matrix - negative;
> 5 pressing - positive.
>
> The above presumably comes from the DECCA/London pressing plant at that
> time.
>
> And I just consider the use of the above to be as common in certain
> quarters
> as Father, Mother, Son is to me.
>
> None of them is wrong one should just be aware that depending on where
> you
> are in the word that different words are used to describe the exact same
> process.
>
> I could just use the word "Working Matrix" to describe the Son or
> Stamper
> and old ones in the production industry would understand at once what I
> meant.
>
> Work part can be used too in a pinch....;-)
>
>
>
> --
>
> Best regards,
>
> Goran Finnberg
> The Mastering Room AB
> Goteborg
> Sweden
>
> E-mail: [log in to unmask]
>
> Learn from the mistakes of others, you can never live long enough to
> make them all yourself. - John Luther
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