Stokowski, The Philadelphia Orchestra and the Bell Laboratories
Experimental Recordings
Stokowski's Interest in Broadcasting Technology
In 1929, the Philadelphia Orchestra began live
broadcasts of concerts from the Academy of Music via the NBC
radio network. Arthur Judson, the famous orchestra manager had been
urging Stokowski to broadcast for some time, but Stokowski was
dissatisfied by the sound of these early broadcasts.
About this same time, Stokowski approached
Dr.
Harvey Fletcher (1884-1981) at the Bell Laboratories seeking ways to
improve this transmission.
Harvey Fletcher and the Bell Laboratories Research in
Recording Technology
Harvey Fletcher was a brilliant physicist who had worked at
the University of Chicago with Nobel Prize winner Robert A.
Millikan (1868-1953). Millikan was famous for his
measurement of the charge of the electron in 1910, and for
his work on the photoelectric effect (confirming Einstein's
theory of the photon theory of light). Millikan
then went on to serve as president of Caltech from 1921 to 1945.
Fletcher received his Ph.D. from the University of
Chicago summa cum laude, working with Millikan on determining
the value of the charge of the electron. Fletcher later became Director of Research
at Bell Laboratories, where he oversaw three decades of research
and improvement in sound, hearing, transmission, and
reproduction.
Stokowski, Harvey Fletcher and Robert Millikan in 1936
13
At Bell Laboratories, Fletcher oversaw research in this area by
Joseph P. Maxfield, Henry C. Harrison, K. P. Secord, Rogers H.
Galt 12, Harold Black (who invented the negative feedback amplifier
in 1927), Arthur C. Keller and others.
Harrison and Maxfield made a number of developments which,
together allowed the creation of an electrical sound recording
system. One of these was the development of a
matched-impedance electronic system, with a carbon microphone,
linked to a tube or valve amplifier, driving a moving magnet
(called also a 'moving armature') cutting head to scribe the
sound in the wax master.
This matched-impedance electrical recording system had a
recording bandwidth from 50 Hertz to 6,000 Hertz, beyond which
its sensitivity declined. This wider bandwidth added another
octave of sound reproduction, compared with the acoustic
process, along with the reduced harmonic distortion and a
generally more realistic sound image.
Harvey Fletcher, K. P. Secord, and Rogers H. Galt at the Bell Laboratories
In a 1981 BBC Radio 3 interview, Arthur C. Keller, who worked for Henry Harrison, told of his early sound and
recording efforts and those of his colleagues in the 1920s and 1930s at the Bell Laboratories. They were working
initially on long line transmission, and later on high fidelity and binaural or stereophonic recording. Keller
spoke of Bell Laboratories work with Stokowski and the Philadelphia Orchestra to achieve high quality recordings
and broadcast transmission from the Academy of Music in Philadelphia in 1930 and 1931.
1930 Advertisement for the Sunday Stokowski - Philadelphia Orchestra broadcast
1931 - Bell Laboratories Experimental Recordings of Stokowski and the Philadelphia Orchestra
In April, 1931, Bell Labs began recording Stokowski and the Philadelphia Orchestra in the Academy of
Music, using new equipment installed in the basement, with Stokowski's permission. This equipment,
did not use the conventional lateral cutting heads used for contemporary 78 rpm disks.
Keller’s disk cutting equipment used a vertical cut (“hill and dale”) recording method, using a magnetic moving
coil pickup fitted with a sapphire stylus cutting the wax master.
The vertical cutting device improved stylus tracking and thereby reduced harmonic distortion. It also helped
to expand the dynamic range of the recording.
Moving coil microphones, capable of frequencies above 10,000 Hz, developed by Bell Laboratories were used in
both the monophonic and 'binaural' recordings. Reportedly, more than 100 78 RPM sides were cut in the
Academy of Music during the 1931 - 1932 Philadelphia Orchestra season.
Bell Labs had also earlier determined that surface noise on 78 wax recording masters (called the “matrix”)
was caused by the graphite which was deposited on the wax surface during the manufacturing process.
In the web page
Eldridge Johnson, Victor, and the Development of Acoustic Recording,
you can read that first lead powder, and later copper powder was brushed on the wax master to make it conductive for
electroplating. Later, graphite was adopted. The graphite allowed the surface of the master to become
conductive, so it could be electroplated, preliminary to the later steps in producing record “stampers”.
As described in '
Eldridge Johnson Develops Electroplating of the Wax Master
', this electroplating technique was the key to permitting creation of multiple versions of "masters"
, used in the mass production of records.
Arthur Keller and A.G. Russell devised the approach
of processing the wax masters by means of gold sputtering, in a vacuum
chamber, which laid down a one molecule thickness of gold onto
surface of the wax. This layer allowed them to electroplate a
copper layer onto the gold, thus bypassing the need for
graphite.
Pressings of the recordings were then made using
cellulose acetate disks, rather than the typical noisy shellac
material of the 78 rpm era.
In December,
1931, the first electrical recordings with this improved process were made and the
experiments continued throughout the 1931-32 concert season. The
audio spectrum was extended first to 9,000 Hz and then to 10,000
Hz, giving for the first time good fidelity in the overtones and
treble range of instruments.
Bell Laboratories asked Arthur Keller to come out of retirement
in 1979 to catalogue, and transcribe some of the gold sputtered
disks still in storage. Keller identified Stokowski -
Philadelphia recordings from among 600 metal masters at the Bell
Laboratories in Murray Hill, New Jersey4. Of
these, more than 100 were preserved by transcription.
With the typically excellent and energetic transcriptions by Ward Marston, many of
the metal masters were saved, cataloged, and transcribed, including some of the stereo
items. Based on Ward Marston and Arthur Keller's work, Bell Telephone issued
two commemorative albums with
some of these transcriptions in 1981. As far as I have
been able to determine, all of the CDs which circulate with some
of this material come from the Bell LP disks compiled by Arthur
Keller and Ward Marston. We are indebted to them for this
work.
The 1981 Bell Laboratories LP of 1931 and 1932 Philadelphia
Performances
1931 Roman
Carnival Overture
The Roman
Carnival Overture was recorded December 5, 1931 in the Academy
of Music, without the knowledge of the orchestra members, who
did not notice, since radio microphones were routinely strung
from the Academy of Music ceiling. Keller had installed
his recording equipment in the basement below the orchestra
stage. Stokowski later said, when he heard the Roman
Carnival recording at the Bell Laboratories in New York City
that it was the best quality recording he had ever heard.
Keller said that
their recorded response in the Roman Carnival extended to 13,000
Hz, the highest to that point achieved by Bell Laboratories5. You may hear
this mono recording by clicking on the link, below.
In March, 1932,
Keller recorded the Philadelphia Orchestra for the first
time in “binaural” or stereo sound, by connecting two
different microphones each to its own cutting stylus, with
each moving magnet cutting stylus in its own arm, each
parallel to the other, but one recording from the outer edge
of the wax disk (as was normal), and the other beginning
half way into the disk, so that each would cut half of the
disk with a right and a left channel.
On March 12, 1932
Stokowski recorded the Scriabin "Poem of Fire" in this
format. This recording is the earliest surviving example of
stereophonic recording.
Alan Blumlein and the development of Electrical and
Stereophonic Recording
Another early
pioneer of stereophonic recording was done at EMI in Hayes,
Middlesex, UK by the brilliant young scientist Alan
Blumlein.
Alan Blumlein in the 1930s
Blumlein had joined the Columbia Graphophone Company in March, 1929
reporting to another great man and engineer, Isaac
Schoenberg (in 1962, Sir Isaac Schoenberg) who had become
General Manager of Columbia in 1928. Schoenberg had
previously been General Manager of the Marconi Wireless and
Telegraph Company.
Sir Isaac Schoenberg
Schoenberg, who had emigrated from Russia to England in 1914,
hired Blumlein to join him at Columbia Gramophone. He
assigned Blumlein the job of
inventing a new electrical recording process not dependent on
the Bell Labs/Western Electric Westrex process. The UK
Columbia company had purchased the failing US Columbia company
in 1924, and had then licensed the Westrex process from Western
Electric (who initial licensed only US firms) in late 1924,
somewhat before the Victor Talking Machine Company. This
may have influenced Victor also to license the Westrex
process.
In 1929 and
1930, Blumlein developed a superior disk cutting technology,
using moving coil cutting heads, rather than the moving magnet
technology of the Westrex process. He also developed a
moving coil microphone at about this time. Interestingly
E.C. Wente of Bell Laboratories also developed a moving coil
microphone in 1928, which was patented (1,766,473) in 19319.
Wente's Western Electric Model 618A of 1931 was nearly flat in
response from 30 to15,000 Hertz, and its low impedance (30 Ohm)
allowed long cables without significant signal loss10.
E. C. Wente Western Electric Moving Coil Microphone Model
618A of 1931
These inventions by Blumlein eliminated the
royalties paid to Western Electric on each disk using the 'Westrex' process.
These inventions are particularly impressive, given that
Blumlein was working for the most part alone, with some
assistants, whereas E. C. Wente,
Joseph P. Maxfield, Henry C. Harrison were working as part of a
large Bell Laboratories team.
Blumlein, as well as saving EMI the Westrex royalty payment,
developed a moving coil cutting head which was superior to the
Westrex system, since it reduced distortion and increased
frequency response, and tended to be more linear in frequency
response during the critical step of cutting the wax master.
In 1931, in part because
of the effects of the great depression, the Gramophone Company
(HMV) merged with Blumlein's employer, Columbia Gramophone
Company (Columbia) to form Electric and Musical Industries:
EMI. In November, 1931, EMI also built the famous new
recording studios at 3 Abbey Road, in St. John's Wood, London,
at that time, the largest recording studios in the world.
In 1933, using
the stereophonic developments which Blumlein patented (patent
issued in June 14, 1933), EMI cut a stereophonic disk with two
channels in one groove, cut 90 degrees apart. Blumlein's
first recording apparatus is described by A. J. Lodge of EMI
Labs, in R. W. Burn's excellent 'The
Life and Times of A D Blumlein'.
"...The stereo wax cutter survives as well. It was made
from two Western Electric moving-armature units coupled to a
single stylus by a lightweight lever system, so that one unit
moved the stylus vertically, and the other horizontally.
The first calibration of the recorder is believed to have been
on 12th July 1933. Bandwidth is reported to have been
about 4kHz.......It was with this set-up that the well-known
'walking' and 'talking' records, the first complex-cut stereo
records ever, were made some time before 16th December
1933......The signals feeding the two cutters were sum, for the
lateral cutter, and difference for the vertical... "
This technique
was similar to Arthur Keller's patent, but slightly different.
Keller's patent, written in 1931 and 1932, but not submitted
until 1936, taught having both channels cut 45 degrees from
vertical, and 90 degrees from each other.
So, Blumlein's pioneering stereo
work resulted in the first pressing of a stereophonic disk with
two channels in one groove.
It is interesting that Keller had
conceived of this 45 degree rotation so that each channel would
have potentially similar reproduction, since he found that
cutting purely vertical and
horizontal groves having differences in reproduction. In
contrast, the first
EMI
stereo disk had one channel cut horizontally, and the other
vertically, like the old 'hill and dale' cutting method of companies
such as Pathé, although Blumlein did later work on 45 degree
oriented groves.
The two channels in one groove, and the 45 degree
orientation seems to have been forgotten until the period 1954 -
1958, when Westrex of
Hollywood, California. Westrex was sold to Litton Industries,
and which prospered for a time in stereo and Hollywood sound
systems. Westrex
developed the stereo Westrex groove design, reinventing the 45
degree orientation (see
The Westrex Stereo Disk System).
Arthur Keller and
the Transcription of the Bell Labs Recordings
So, these
pioneering Bell Labs - Stokowski recordings of March 12, 1932 are
the oldest stereo recordings we have. You may hear two stereo
tracks transcribed in 1980 by Arthur Keller from the old metal
masters at the Bell Labs, of the "Poem of Fire"
by Alexander Scriabin (1874 - 1915), below.
Keller later
thought of the idea of recording the two channels of a stereo
recording in one record groove each at 45 degrees from vertical
and 90 degrees from each other. Keller was awarded US patent
2,114,471 for this method, which was re-invented in the 1950 for
the Westrex stereo recording process.
The 1931 and
1932 experimental stereophonic recordings were made employing
two cutting styli making two separate grooves in the wax master,
one starting at the disk edge (as was normal), and the other
starting at the middle of the wax master. 125 of these Bell
Labs/Philadelphia Orchestra test recordings of 1931 and 1932
have been preserved. Some are stereophonic and others are
extended range monophonic. The March, 1932 stereophonic
recordings are the oldest stereophonic recordings to have
survived.
In 1933, EMI,
using the stereophonic developments patented by the brilliant
Alan Blumlein, cut a stereophonic disk with two channels in one
groove, cut 90 degrees apart, as with Arthur Keller's patent.
However, Keller's patent taught having both channels cut 45
degrees from vertical, whereas the EMI disk had one channel cut
horizontally, and the other vertically, like the old 'hill and
dale' cutting method of companies such as Pathé.
Thanks to restoration work
supervised by Arthur Keller himself and funded by Bell Labs, a
limited edition album of some of these 1931 and 1932 masters was
released in 1980. In restoring these historic recordings,
Keller did not use the original cellulose acetate pressings, but
rather worked directly from the master “mother” disks, which are
essentially the negative images of the disk pressing. The
“negative” grooves are raised up from the master's surface, and
these would have formed the record grooves if pressed into the
record material.
For this reason, Keller used a
stylus shaped like a fork, which would ride on the top of the
raised, negative grooves, with the turntable revolving
“backwards” since the disk is a negative of the finished 78 rpm
disk.
1933 Long Distance Concert - Philadelphia to Washington
On April 27, 1933, Bell Labs, Harvey Fletcher and Arthur Keller also
arranged long distance transmission of high quality stereophonic sound
across telephone long lines capable of sound transmission up to 10,000
Hz. It is interesting to note that what must have been the first telephone
transmission of music also involved the Academy of Music. As cited in
Music in Philadelphia, "...Mr.
Bocovitz, the renowned pianist, played...Home Sweet Home...and other
airs in New York. The audience heard this program via telephone at
the Academy of Music in Philadelphia." 11
A concert of the Philadelphia Orchestra at the Academy of Music,
sponsored by AT&T was captured by
three microphones spaced across the front of the orchestra and
transmitted via three long lines to Constitution Hall in Washington,
D.C. where three amplified loudspeakers reproduced the orchestra
sound. The orchestra was conducted by Alexander Smallens,
assistant conductor of the Philadelphia Orchestra, with
Stokowski controlling sound balance.
Stokowski at the controls in the 1933 Washington DC stereo broadcast
with Harvey Fletcher observing
The Washington DC broadcast concert was advertised as demonstrating “…the
recent advances in high-quality telephonic transmission and
reproduction of music…" On April 9 and April 10, 1940,
Harvey Fletcher and Stokowski arranged another demonstration of
stereo sound in Carnegie Hall with music recorded onto a three channel
system using sound recorded optically on film with a frequency range of
30 Hz to 15,000 Hz.
Sources:
4 page 805 Journal of the Audio Engineering
Society. Volume 31 no 10. October, 1983.
11 page 160. Gerson, Robert A.
Music in Philadelphia Theodore Presser Co. Philadelphia. 1940.
12 Thanks to Christine Rankovic, Ph. D.
for this information on Rogers Harrison Galt.
13 Photograph
from Harvey Fletcher "My work with Millikan on the oil-drop
experiment" Physics Today. American Institute of Physics, College
Park, Maryland, USA June 1982. Again, thanks to Christine Rankovic, Ph. D. for
this material
If you have any comments or questions about this Leopold Stokowski site, please
e-mail me (Larry Huffman) at e-mail address:
leopold.stokowski@gmail.com
