Инструкции Пользователя для MartinLogan ElectroMotion® ESL C

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performed splendidly. 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. The acoustic gramophone 
was destined to become obsolete.
Due to Rice and Kellogg’s enthusiasm, they 
devoted a considerable amount of time 
researching the electrostatic design. However, 
they soon encountered the same difficulties that 
even present designers face; planar speakers 
require a very large surface area to reproduce 
the lower frequencies of the audio spectrum. 
Because the management 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 
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 experienced 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.
In 1947, Arthur Janszen, a young Naval engineer, 
took part in a research project for the Navy. 
The Navy was interested in developing a better 
instrument for testing microphone arrays. The test 
instrument needed an extremely accurate speaker, 
but Janszen found that the cone speakers of the 
period were too nonlinear in phase and amplitude 
response to meet his criteria. Janszen believed 
that electrostats were inherently more linear than 
cones, so he built a model using a thin plastic 
diaphragm treated with a conductive coating. This 
model confirmed Janszen’s beliefs, for it exhibited 
remarkable phase and amplitude linearity.
Janszen was so excited with the results that he 
continued research on the electrostatic speaker 
on his own time. He soon thought of insulating the 
stators to prevent the destructive effects of arcing. 
By 1952, he had an electrostatic tweeter element 
ready for commercial production. This new tweeter 
soon created a sensation among American audio 
hobbyists. Since Janszen’s tweeter element was 
limited to high frequency reproduction, it often 
found itself used in conjunction with woofers—
most notably, those from Acoustic Research. 
These systems were highly regarded by all audio 
enthusiasts.
As good as these systems were, they would soon 
be surpassed by another electrostatic speaker. 
In 1955, Peter Walker published three articles 
regarding electrostatic loudspeaker design in 
Wireless World, a British magazine. In these 
articles, Walker demonstrated the benefits of 
the electrostatic loudspeaker. He explained that 
electrostatics permit the use of diaphragms that 
are low in mass, large in area and uniformly 
driven over their surfaces by electrostatic forces. 
Due to these characteristics, electrostats have the 
inherent ability to produce a wide bandwidth, flat 
frequency response with distortion products being 
no greater than the electronics driving them.
By 1956, Walker backed up his articles by 
introducing a consumer product, the now famous 
Quad ESL. This speaker immediately set a 
standard of performance for the audio industry 
due to its incredible accuracy. However, in actual 
use, the Quad had a few problems. It could not be