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In the late 1800’s, any loudspeaker was considered exotic. 
Today, most of us take the wonders of sound reproduction for 
granted.

It was 1880 before Thomas Edison had invented the first 
phonograph. This was a horn-loaded diaphragm that 
was excited by a playback stylus. In 1898, Sir Oliver 
Lodge invented a cone loudspeaker, which he referred to 
as a “bellowing telephone”, that was very similar to the 
conventional cone loudspeaker drivers that we know today. 
However, Lodge had no intention for his device to reproduce 
music because in 1898 there was no way to amplify an 
electrical signal! As a result, his speaker had nothing to offer 
over the acoustical gramophones of the 
period. It was not until 1906 that Dr. 
Lee DeForrest invented the triode vacu-
um tube. Before this, an electrical signal 
could not be amplified. The loudspeak-
er, as we know it today, should have 
ensued then, but it did not. Amazingly, 
it was almost twenty years before this 
would occur.

In 1921, the electrically cut phonograph record became 
a reality. This method of recording was far superior to the 
mechanically cut record and possessed almost 30 dB of 
dynamic range. The acoustical gramophone couldn’t begin 
to reproduce all of the information on this new disc. As a 
result, further developments in loudspeakers were needed to 
cope with this amazing new recording medium.

By 1923, Bell Telephone Laboratories made the decision 
to develop a complete musical playback system consisting
of an electronic phonograph and a loudspeaker to take 
advantage of the new recording medium. Bell Labs 
assigned the project to two young engineers, C. W. Rice 
and E. W. Kellogg. 

Rice and Kellogg had a well equipped laboratory at their 
disposal. This lab possessed a vacuum tube amplifier 
with an unheard of 200 watts, a large selection of the 
new electrically cut phonograph records and a variety of
loudspeaker prototypes that Bell Labs had been collecting 
over the past decade. Among these were Lodge’s cone, a 
speaker that used compressed air, a corona discharge (plas-
ma) speaker, and an electrostatic speaker.

After a short time, Rice and Kellogg had narrowed the field 
of “contestants” down to the cone and the electrostat. The out-
come would dictate the way that future generations would refer 
to loudspeakers as being either “conventional” or “exotic”.

Bell Laboratory’s electrostat was something to behold. This 
enormous bipolar speaker was as big as a door. The dia-
phragm, which was beginning to rot, was made of  a pig 
intestine that was covered with fine gold leaf to conduct the 
audio signal.

When Rice and Kellogg began playing the new electrically
cut records through the electrostat, they were stunned and 

impressed. The electrostat performed splen-
didly. They had never heard instrumental 
timbres reproduced with such realism. 
This system sounded like real music rather 
than the honking, squawking rendition of 
the acoustic gramophone. Immediately, 
they knew they were on to something big.
T h e   a c o u s t i c   g r a m o p h o n e   w a s 
d e s t i n e d   t o   b e c o m e   o b s o l e t e .

Due to Rice and Kellogg’s enthusiasm, they devoted a 
considerable amount of time researching the electrostatic 
design. However, they soon encountered the same difficul-
ties that even present designers face; planar speakers require 
a very large surface area to reproduce the lower frequen-
cies of the audio spectrum. Because the management at Bell 
Labs considered large speakers unacceptable, Rice and 
Kellogg’s work on electrostatics would never be put to use 
for a commercial product. Reluctantly, they advised the Bell 
management to go with the cone. For the next 30 years, the 
electrostatic design lay dormant.

During the Great Depression of the 1930’s, consumer audio 
almost died. The new electrically amplified loudspeaker 
never gained acceptance, as most people continued to 
use their old Victrola-style acoustic gramophones. Prior to 
the end of World War II, consumer audio saw little, if any,
 progress. However, during the late 1940’s, audio expe-
rienced a great rebirth. Suddenly there was tremendous 
interest in audio products, and with that, a great demand 
for improved audio components. No sooner had the cone 
become established than it was challenged by products 
developed during this new rebirth.

Electrostatic History     17