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From: Patent Tactics, George Brock-Nannestaed


Hello Joe,


my previous comment was somewhat garbled, so here I go again and with an 
important technical addition.

 - indeed, someone made equipment, and it was aimed at the many, many copper
negatives held by the Phonogramm-Archiv in Berlin. It was an experiment 
described (with photographs) in the following article:

Gerd Stanke and Thomas Kessler: "Procedure to Recover Sound Signals From the
Negative Tracks in Copper Negatives of Edison Cylinders in an Image 
Analysis/Sensorial Way (SpuBiTo)", in  (Arthur Simon, Ed.) 'The  Berlin 
Phonogramm-Archiv 1900-2000. Collections of Traditional Music of the
World.',
VWB - Verlag für Wissenschaft und Bildung, Berlin 2000, pp. 209-215.

The main problem was one of fitting the distorted microscope images to a
long
string of non-distorted images. At the time, the scanning time was 80
minutes
for one cylinder negative. However, there is presently a product offered by 
the developers GFaI (Gesellschaft zur Förderung angewandter Informatik
e.V.);
try to google the strange word "SpuBiTo" - today I had 135 hits.

Now, when I wrote the above I thought that the process was contact-less. 
Studying the GFiI brochure at first I thought that a diamond stylus they 
mention rides between the ridges to define where the grooves are. However, 
reading the text in view of the 2000 article mentioned above, I am now 
convinced that the stylus actually rides on the top of the ridges, controlled
by the image capture, so that is is a mechanical tracking after all. It is a
vertical position measuring system. It is very gentle mechanical tracking, 
but it is then much more similar to the Kyiv system used for ordinary 
cylinders.

Hence, we still only use part of the information content in these ridges 
(i.e. originally grooves).

The background noise from copper negatives would have two sources.

1) from the metallisation of the original - not all used the Edision 
gold-sputtering process

2) from the galvanotypic process: if your deposit current was too large, you
would have large crystals, and the edges would make a noise. The rule was 
"start slowly, to build a quiet layer, and then increase the current to
build
thickness". However, if you were in a hurry - - - - -.

Not to mention that sometimes the researchers at the Berlin archive played 
the cylinder before the galvano process - - - - 

Best wishes


George

----------------------------------------

> So galvanos were used to make cylinders but were not themselves 
> reproducible, unlike metal parts for a disc.
> 
> Or did someone design a machine to play them? It would be fascinating to 
> hear a cylinder recording made from metal parts, assuming that they 
> would be as quiet as their disc counterparts.
> 
> joe salerno
> 
> On 3/29/2012 10:38 PM, Michael Biel wrote:
> > On 3/29/2012 4:54 PM, David Lewis wrote:
> >> BTW the galvanos used by the Berlin Phonogrammarchiv to mass produce
> >> copies
> >> of ethnological cylinders were, in effect, metal cylinders. But they
> >> represented the negative image of the groove, and the grooves
> themselves
> >> were inside the galvano. Dave Lewis Lebanon, OH
> >
> > Of course that is how ALL mass produced cylinders were made. I have a
> > metal mould that was used to make one of the Ediphone Dictation lesson
> > cylinders as late as the 1950s.
> >
> > Mike Biel [log in to unmask]
> >>
> >> On Thu, Mar 29, 2012 at 9:49 AM, [log in to unmask]<
> >> [log in to unmask]> wrote:
> >>
> >>> Metal cylinders? Someone please tell me more about these. Who made
> them
> >>> and when?
> >>>
> >>> joe salerno
> >>>
> >>>
> >>> On 3/29/2012 7:30 AM, Chris J Brady wrote:
> >>>
> >>> Throughout his career, Lomax was always using the latest
> >>>> technology to record folk music in the field and then share
> >>>> it with anyone who was interested. When he started working
> >>>> with his father, John Lomax, in the '30s, that meant
> >>>> recording on metal cylinders.
> >>>>
> >>
> >
> 
> -- 
> Joe Salerno