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Re: [ARSCLIST] Magnetic Recording History (was OTR online?



Hi George and others:

It seems like those BIOS reports would be at the British Library or a UK government archive. Perhaps a listmember in the UK could track down photocopies. I'd be happy to scan them and, assuming they are in the PD, perhaps the AES Historical Committee would be interested in hosting them? I will check into that if we can track down a copy for scanning. Some Googling last night netted nothing readily available online.

-- Tom Fine

----- Original Message ----- From: "George Brock-Nannestad" <pattac@xxxxxxxx>
To: <ARSCLIST@xxxxxxxxxxxxxxxx>
Sent: Friday, January 02, 2009 6:42 PM
Subject: Re: [ARSCLIST] Magnetic Recording History (was OTR online?



From: Patent Tactics, George Brock-Nannestad


Richard Hess gave us a lot of information that needs to be constantly
repeated, or myths will survive.

I did an attempt at myth-busting in a Letter to the Editor of the JAES, while
Jack Mullin was still around:

"Comments on -The History of Magnetic Recording- and Author's Reply"
JAES Volume 29 Issue 7/8 pp. 524-525; August 1981

The Author had been John T. Mullin, who wrote:

"Magnetic Recording for Original Recordings"
JAES Volume 25 Issue 10/11 pp. 696-701; November 1977

but apparently it has not helped a bit: I argued that the development of the
procedure was no secret, that scientific Journals like Akustische Zeitschrift
that were subscribed to outside Germany were freely available, and that the
procedure was patented. The inventors Weber and his boss von Braunmühl were
jubilant in the press releases. I think that the fact that this knowledge was
apparently not present when German radio stations were taken proves
difficulties in disseminating the information among the Allies.

Apart from bringing home Magnetophons in pieces, as Mullen famously did, the
British Intelligence Objectives Sub-Committee and the Field Infomation
Agency, Technical rounded up scientists and engineers in Germany 1945-47,
interviewed them and copied and translated copious amounts of documents for
publicly available reports, many of which are now forgotten, in all areas of
endeavour. All US patents belonging to the Axis powers had been confiscated
from (if I recall correctly) 1941 and were available for the war effort at a
license fee of US$1 (one). After 1949, when Western Germany was created, all
these permissions to use became null and void.

The two most important documents relating to the present discussion are:

"The magnetophon sound recording and reproducing system"
B.I.O.S. Final Report No. 951
based on several trips 1945-46

"Plastics in German sound recording systems"
B.I.O.S. Final Report No. 1379
based on an expedition lasting a month in 1946

These are essential reading, and they are in English. But there are several
more.

Kind regards,


George


P.S. Lorenz AG was completely independent from AEG, which later became
related to Telefunken (and Lorenz became part of Standard Electric). The
Magnetophon GmbH was formed as a 50/50 ownership company by AEG and I.G.
Farbenindustrie (which in itself was an industry conglomerate of dye and
chemical industries, including Agfa).

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


Richard Hess wrote:


For the record, the full name of AMPEX's founder
is Alexander M. Poniatoff. It is my understanding
that AMPEX came from Poniatoff's initials plus
the first two letters of the word EXcellence.

At 03:27 AM 2009-01-02, Michael Biel wrote:

>Second, that Hitler story is laughable.  Hitler
>would "be" where ever the broadcast announcer
>said he was!!!  Besides, Hitler was not making
>many speeches during the war.  The sound quality
>of distant radio reception would mask any
>differences between a speech recorded on tape and a speech recorded on
disc.

The version of this story that I heard was that
Mullin and other Signal Corpsmen heard late night
orchestra broadcasts of some length and thought
that the sound quality was better than any
long-form transcription device they had so they
were interested in learning about this German
technology after the war. They thought the
recordings sounded live, but wondered if even
Hitler would schedule musicians to play in the middle of the night.

I concur with Tony that early AM radio sounded
much better than what we hear today. I recall
owning a tube Zenith AM/FM radio that was
reasonably high-fidelity in the 1950s--even on
AM, and having my first exposure to the "Texaco
Metropolitan Opera Radio Network" via WOR on the AM band.

>Lastly, the entire first season of Philco Radio
>Time was recorded and edited on DISC.  Tape was
>only used for mastering and editing starting in
>the second season, and even then the tapes were dubbed to disc for
broadcast.

The first show recorded on tape was broadcast
1947-10-01 (which was the start of the 1947-1948
season). While the original tape went missing
from the Ampex Collection prior to it being
transferred to Stanford (it would be on a 14"
Ampex NAB-hub reel in all likelihood), excellent
2nd generation copies remain. One of those has
been digitized and delivered to the Stanford Ampex Collection.

No one at ABC wanted to risk going with tape
live-to-air due to the fragility of the early
tapes with multiple splices as well as having
only two of Mullin's modified Magnetophons to
play them on. Mullin shipped the transports and
heads home but did not bother with the
electronics as he saw improvements that he could
make right away. Mullin's electronics have one
additional tube as compared to the original AEG
electronics with AC bias that he left behind.

At 10:51 AM 2009-01-02, Anthony Baldwin wrote:

>In Germany this situation changed irrevocably in 1941 when AEG
>engineers von Braunmühl and Weber stumbled across AC tape bias, where
>the addition of an inaudible high-frequency tone resulted in a
>striking improvement in sound quality - something that was radical
>enough to be discernible in prerecorded German AM broadcasts, if the
>BBC's Caversham Park wartime monitoring reports are to be credited.
>
>In fact, this is not so hard to believe, as the generous bandwidth of
>national AM channels in the 1930s and '40s offered a far higher level
>of AM fidelity than we're used to today. Nazi speeches aside, the
>technical leap forward was most glaringly obvious in prerecorded
>broadcasts by the likes of Fürtwängler and the Berlin Philharmonic,
>as recent CD reissues have adequately confirmed.

For a more detailed discussion, please see
Engel, Friedrich Karl.
<http://www.richardhess.com/tape/history/Engel--Walter_Weber_2006.pdf>Walter
Weber's Technical Innovation at the Reichs-Rundfunk-Gesellschaft
and
Engel, Friedrich Karl and Peter Hammar,
<http://www.richardhess.com/tape/history/Engel_Hammar--Magnetic_Tape_History
.pdf>A
Selected History of Magnetic Recording

There may be additional items of interest at
http://www.richardhess.com/tape/history/

>While Jack Mullen may have been able to kickstart Ampex by sending
>home a couple of these liberated machines in bits via the no-doubt
>bemused Army Post Office, the final broadcast requirement for tape -
>superior editability - was only really achieved when the notoriously
>fragile German acetate-backed "paper" tape could be abandoned in
>1947-48 in favor of 3M's new, sturdier #111 stock. From that moment
>on tape was definitely superior to disc as a studio medium, even if
>Bing's transcriptions were still pressed up as discs.

That is partially true in that the German tape
that Mullin brought back was fragile but more in
the context that he had only about fifty reels
(most of which survive in various states of
repair in the Stanford Ampex Collection) and they
were cut and spliced and recut and respliced
until 3M came up to speed with tape
manufacturing. Audio Devices also supplied some
tape at this time or shortly thereafter (we found
some spliced in with some of the German tape).

However, paper tape was abandoned circa 1935 in
Germany while it was still made for the Brush
Soundmirror and sold directly by 3M (Scotch)
until some time in the 1950s in North America.
Utah recorders in Canada also sold paper tape.

The German tape from 1935-1944 was an
acetate-based tape called Magnetophonband Typ C.
The factory where this was manufactured was
destroyed in an industrial accident (not a
war-related explosion) and from 1944 until the
end of the war, only homogeneous PVC
Magnetophonband Typ L tape was available. In the
Typ L tape, the gamma ferric oxide was embedded
in the PVC matrix and not coated on the basefilm
like current and preceding tapes. The "Typ L"
refers to IG Farben's trade name "Luvitherm" for
their brand of PVC, just as "Mylar" became
perhaps better known than PET for this later basefilm.
http://www.wipo.int/ipdl/en/madrid/key.jsp?KEY=453247
http://heritage.dupont.com/touchpoints/tp_1952/overview.shtml

Most of the Magnetophonband tape has survived
well. Some of the Typ C is starting to exhibit
signs of vinegar syndrome, but this has occurred
mostly with ones stored in the steel film-style
cans than in the cardboard (press board?) boxes that most of them came in.

Some of the Typ L tape is showing some structural
weakness and, as with many plastic films, shows a
tendency to tear when edge nicks have occurred.
Sometimes, splices would catch at the tape edge
and start a long tear at a very shallow diagonal.
In one case, the tear was about half a metre
long. Repeated playing of this tape on the
less-than-completely gentle original Magentophon
in the Pavek collection has caused some pinholes
to occur in the Typ L tape where clumps of the
oxide material have fallen out of the PVC film matrix.

You may also enjoy reading my paper on the
playback effort for some of these tapes. As of
2008-08, all of these have been delivered to both
Stanford and the Pavek Museum and we included 101
(IIRC) different items in the collection, most
were on the original Magnetophonband. These have
been ingested into Stanford's Digital Repository
system. I am not sure about access.
Hess, Richard L.
<http://www.aes.org/journal/suppmat/hess_2001_7.pdf>The
Jack Mullin/Bill Palmer Tape Restoration Project

Since there was additional material in the Pavek
Museum collection, including Magnetophonband from
other collectors, I concatenated the the
Mullin-Palmer collection, the Mullin family
collection, and the Pavek collection plus a few
other related items into one collection for the
sake of looking at these early tapes. The
original material for the Mullin-Palmer
collection resides at Stanford, while the Mullin
family collection is retained by the family, and
the Pavek retains its own collection. I have
recorded the 1947-10-01 show back onto some
new-old-stock Magentophonband Typ L for
demonstrations at the Pavek and I need to make
one or two more copies for them on NOS material I still have from the
Pavek.

Cheers,

Richard

Richard L. Hess                   email: richard@xxxxxxxxxxxxxxx
Aurora, Ontario, Canada       (905) 713 6733     1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.


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