From: Patent Tactics, George Brock-Nannestad
> Thanks for that info-tidbit.
> Another question -- record-cutting guys talked about laquer having a little
> bit of a "rebound" or
> "memory," where the groove would not end up exactly as it was cut because
> the laquer would move back
> toward its original state in the short time it took to harden following the
> hot-stylus cut. Guys I
> knew who went back to cutting on wax, including my father, said this was not
> so with wax but of
> course there were other issues to contend with. So with DMM, do you
> eliminate the "rebound" or
> "memory" issues because metal is a harder and more stable material?
----- the rebound was actually the cause of several problems. One was that
the vertical cutting angle in the finished record was changed, adding to the
change by flexing in the cutting stylus mechanism. The other was groove pre-
and postecho. This was discussed extensively in yet another JAES article that
I have to find the reference to.
In DMM, there was established a resonance between the cutting stylus and the
copper creating a vertical modulation at ca. 80 kHz, and you virtually
chipped away at the material, so there was no rebound at all. Somewhere (I
have forgotten where) there was a belief that there was a separate high
frequency generator--there was not.
I have not kept up with the still working DMM installations world-wide.
Several places had their own galvano plant made according to the Teldec
design for making blanks; in the US this was via Gotham Audio. Smaller places
used to buy them from Teldec, at least in Europe; in cold storage they could
last a year. In 1997 there was certainly one place in New York that had that:
> ----- Original Message -----
> From: "George Brock-Nannestad" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, January 12, 2010 11:06 AM
> Subject: Re: [ARSCLIST] Cataloging of metal parts
> From: Patent Tactics, George Brock-Nannestad
> Tom Fine wrote (in acknowledgement of Michael Shoshani's reply to my over-
> complete and well-documented reply to what Mike Biel and Göran Finnberg
> written (which was in itself well-documented)
> > This is the common terminology in the US music/recording business that I
> > exposed to, most of the
> > people I know having practiced their craft in the 50's thru the 70's, ie
> > prime LP years. In the
> > US, the thing that stamped LPs in a hot press was commonly called a
> > "Son" seems to be a
> > European term primarily. But it does make sense as far the "mother" and
> > "father" analogy.
> > Here's a question for the disk-cutting experts -- how does it work with
> > direct-metal master? Do
> > you save two generations of plating or is it the same number of plating
> > get to the pressing
> > stamper/son?
> ----- oh, you save, and this reduces the noise. Both, because the inherent
> noise in DMM is lower and because you do not get two generations of
> grain boundary noise. And obviously, this is cheaper per run (although the
> investment in equipment was originally larger). However, I have yet to
> about a direct-to-disc direct-metal master recording. Does anybody out
> know if that has ever been tried? I have used blank DMM masters in the
> Berliner etching process--much better than zinc.
> Kind regards,
> > -- Tom Fine
> > ----- Original Message -----
> > From: "Michael Shoshani" <[log in to unmask]>
> > To: <[log in to unmask]>
> > Sent: Monday, January 11, 2010 10:42 PM
> > Subject: Re: [ARSCLIST] Cataloging of metal parts
> > > On Tue, 2010-01-12 at 01:49 +0100, George Brock-Nannestad wrote:
> > >
> > >> p. 182: 'The obverse impressions of the original matrix are called
> > "mothers"
> > >> in the trade, in view of their office in reproducing matrices from
> > >> "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
> > but
> > >> the 'mother' indeed reproduces.
> > >
> > > I've heard "father" from some but never "son". I first learned the
> > > terminology over 30 years ago reading Roland Gelatt's "The Fabulous
> > > Phonograph", and in both his and Oliver Read's nomenclature it was:
> > >
> > > 1. Original wax (or lacquer) recording is the master
> > > 2. The metal negative plated from the master is the matrix
> > > 3. The metal positive pulled from the matrix is the mother
> > > 4. The metal negative made from the matrix is the stamper
> > >
> > > And these are the terms I have been using since about 1974, when as a
> > > lad of nine years old I was first bitten by that wheezy apparatus that
> > > sounded like a parrot with a cold in the head.
> > >
> > > MS
> > >