Heinz Thiele chaired a session on "Audio History and Technology" at the 94th AES Convention in Berlin in 1993 March. Twelve papers were read, and a magnetic tape stereo recording from 1943 was played to demonstrate the progress of the technology up to that date. The authors, titles, and abstracts of the papers are given below.
Although the papers from this session were never published in the AES Journal, there were English-language convention papers (preprints) of eleven of the papers. In addition, all twelve papers were published in a German-language book that was sold at the 94th Convention, as was a CD of the recordings which were originally made in 1943.
The AES Historical Committee has now arranged to make the preprint set, the German-language book, and the CD more readily available.
The AES Special Publications office has prepared a special-collection Adobe Acrobat PDF file containing all of the eleven English-language preprints from this session, and it is now available for download. The price to AES members is $20 ($30 to non-members).
The German-language book is entitled "50 Jahre Stereo-Magnetbandtechnik: Die Entwicklung der Audio Technologie in Berlin und den USA von den Anfängen bis 1943 " ("50 Years of Stereo Magnetic Tape Engineering: The Development of Audio Technology in Berlin and the USA from the Beginning up to 1943").
The CD produced from the stereophonic recordings mentioned in the last paper is entitled "The 50th Anniversary of Stereophonic Tape Recording".
The AES 94th Convention Report (AES Journal Vol 41, Nr 5, 1993 May, pp 370...380) describes the historical presentations at that convention, and shows four photographs of the equipment displayed. The introduction to the "Audio History and Technology" session, and the English titles and abstracts of the papers, are reproduced below from that Journal, pp 390, 391, 397, 398.Introduction to the Session -- Heinz H.K. Thiele
The first stereophonic recording with two separate channels on one magnetic tape were made in 1943. This was planned and executed by members of the Reichs-Rundfunk-Gesellschaft (RRG) in Berlin. The recorder consisted of an AEG Magnetophone K7 tape transport, equipped with two-track recording and reproducing heads, two V7b recording amplifiers modified for ac-bias, and two V5 reproducing amplifiers. Three Neumann condenser microphones were used for the sound pickup.
With that technology and equipment, excellent frequency response, nonlinear distortion, and dynamic range were achieved. Approximately 200 recordings, mainly of classical music, were made at the RRG. Only five of these recordings remain in existence today -- the others could not be found after World War II.
Fifty years ago consumer stereo reproducers did not exist, and only monophonic radio transmission was possible. However, playback equipment could be set up so that the stereophonic recordings could be played, for example, in hospitals. On the occasion of the fifty-year anniversary of this important step in magnetic recording, the AES 94th Convention will present and describe these historic recordings. A live playback of the recordings will take place at the end of the historical session.
In the twelve paper presentations, the authors will show the development of magnetic audio recording and storage technology to 1943, beginning in the USA and continuing with audio technology in Berlin. The authors will speak about the first principles and the resulting components of magnetic recorders, which led to astonishing results even from today's point of view. Historical equipment, apparatus, and components are exhibited during the convention in conjunction with this session.
[From the Convention Program in the AES Journal, edited by J McKnight]Audio Technology in the United States to 1943 and Its Relationship to Magnetic Recording -- Mark Clark
This paper reviews the history of the development
of audio technology in the United States from its origins in Alexander
Graham Bell’s telephone to the wartime work of the American electronics
industry. It includes a comprehensive review of American contributions,
including developments in electronic amplifiers, microphones, loudspeakers,
and phonographic, optical, and magnetic recorders. The paper will place
these technical developments in the overall context of American developments
in audio engineering during this period, and will show how social and economic
factors retarded the growth of magnetic recording technology in the United
Preprint No: 3481
The history of Berlin of the past 100 years shows
a great many names, inventions, and developments in the fields of science,
fine art, and technology. This also refers to audio with regard to telephone,
film, disk records, radio, and television. For the electroacoustic transmission,
the microphone is the first link of a long chain. This presentation addresses
the contributions made in Berlin from 1880 through 1943, up to the development
of this transducer. Discussed will be the simple carbon granule microphone,
the Reisz microphone, the rf-condenser microphone, the kathodophone, the
ribbon microphone, and the condenser microphones with dc polarization.
Preprint No: 3482
In 1908, R.V. Lieben invented the Electronic Relais,
a bulb in which an electric current could be modulated by a grid electrode.
Soon the new principle was improved upon. During the second decade of the
century, the process of developing electron tubes for radio transmitters
and receivers was amazing. Twin and triple systems connected internally
in one bulb were the beginning of integrated circuits, used in amplifiers
and receivers. By improving the performance stability tubes, more complex
electronics problems could be solved.
Preprint No: 3483
The development of audio amplifier techniques from
the beginning (for example the Lieben one-tube amplifier) to the amplifiers
of the Reichsrundfunkgesellschaft (RRG V5, RRG V 7b) will be explained
by specific examples. The special tasks, the basic functional principles,
as well as the date and the circumstances of the applications will be explained.
Preprint No: 3484
In 1877, Werner von Siemens invented the electronic
acoustic transducer based on the electrodynamic principle—according to
the principle of the plunger coil generally applied today. Initially the
transducer was used as a telephone receiver. With the appearance of power
amplifiers around 1920, the Siemens laboratories began to manufacture a
number of different designs, which eventually gave rise to the loudspeaker
combination Euronor of Klangfilm GmbH in 1937. Other trend-setting loudspeakers
by Berlin inventors worthy of mention include the electroacoustic Statophon
by Hans Vogt, dating from 1921 and the O 15 with coaxial bass and treble
chassis, by Hans Eckmiller, used at RRG Studios from 1943 onward.
Preprint No: 3485
Around the turn of the century, Berliner’s phonograph
record, parallel to Edison’s cylinder, had established a firm footing all
over the world. What had originally been a curiosity could be found in
millions of homes. However, apart from the name “Berliner” and the fact
that numerous firms were producing both cylinders and disks and players
in large quantities in Berlin, the city took no part in the promotion of
this new entertainment medium. It was only in the special utilization of
the phonograph record as the sound carrier for the acoustic accompaniment
of “living pictures” (as movies were called in their early beginnings),
that original ideas began to emerge from the German capital.
Preprint No: 3486
Optical sound track recording has a history of over
100 years. A survey of the fundamental steps of progress is given. The
landmarks described include: the variable-density technique by Ruhmer;
the technology and techniques of the Triegon system and its importance
to the following development; the foundation of the Klangfilm GmbH by Siemens
and AEG; and the Eurocard-recorder and the Klarton voiceless system. The
origins of the analog stereophonic optical sound are discussed.
Preprint No: 3487
In 1900, the Berlin company Mix & Genest began
manufacturing magnetic sound recorders. The further development of Poulsen’s
Telegraphon did not take place until tube amplifiers became available in
the early 1920s. Typical Berlin recorders, all of them with information
carriers made of steel, were the Vox dictating machine, the Stille SEPMAG
transport, the Echophone Dailygraph, and the Lorenz Stahlton-Bandmaschine
(Steeltone-Tapemachine). In 1935 the AEG Magnetophon K1 started the magnetic
tape era and by introducing ac biasing in 1940 and two-channel stereophonic
technology in 1943, a previously unknown reproduction quality was obtained.
Preprint No: 3488
The first official radio transmission in Germany
took place in October 1923, broadcast from a small studio which was acoustically
prepared on a temporary basis with horse blankets, crumpled silk paper,
and curtains. For the recording, a Reiss microphone was used, as well as
a VOX phonograph which irradiated the sound via a trumpet directly into
the microphone. The VOX building at Postdamer Platz in Berlin was full
of studios with different acoustical properties, such as the so-called
Schaeffer tent. In 1931 the Broadcasting House (Haus des Rundfunks) was
opened with new studios and the first large recording studio for symphony
orchestras. The first microphone was that of Reiss in 1864. Together with
the telephone of Graham Bell, the first acoustical transmission took place
when the Eiffel Tower was completed in Paris in 1881. Recording and transmission
techniques, sound absorption and sound-proofing, cinemas, and the first
radio studios will be described as well as the work of the architects,
artist and technicians who opened the way for the new media: radio.
Preprint No: 3521
Walter Weber (1907-1944) was one of the highly innovative
engineers at the Reichs-Rundfunk-Gesellschaft (RRG), or German Broadcasting
Company. Judging from today's vantage point, his most important contribution
to the development of audio technology was the implementation (not the
invention) of high-frequency biasing in practice. With this single stroke,
magnetic recording became the most favorable method in sound recording,
both in terms of reliability and quality. Subsequently, Weber combined
magnetic tape recording and stereophony, reflecting the advanced state
of recording technology at RRG at the time.
Preprint No: 3522
The age, the historical and the artistic relevance,
and the specific history of RRG tapes draw immediate attention to their
preserved state. This paper describes these tapes within the general framework
of magnetic tape preservation. In addition, the paper develops perspectives
for more intensive studies into the field of preservation and rejuvenation
of historical tape materials.
Preprint No: 3523
Almost exactly 50 years before this (1993) Convention,
on April 6, 1943, the first 2-channel recording had been made in the SFB
concert hall. This documentary recording had been lost and has now been
returned to Berlin. Far more important stereophonic recordings from 1944
are Beethoven's Piano Concerto No. 5 (Walter Gieseking) and the final movement
of Bruckner's 8th Sinfonie (Herbert von Karajan). Helmut Krueger, the former
Sound Engineer will talk about the origin of these tracks as well as Hans-Ludwig
Feldgen, the Sound Engineer of the first Stereophonic Live-Broadcast.
No Preprint Available
Jay McKnight, Chair
AES Historical Committee
Ver 4, 2003-01-23, rev 2007-01-05