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due to its incredible accuracy. However, in actual
use, the Quad had a few problems. It could not be
played very loud, it had poor bass performance, it
presented a difficult load that some amplifiers did
not like, its dispersion was very directional and its
power handling was limited to around 70 watts.
As a result, many people continued to use box
speakers with cones.
In the early 1960’s Arthur Janszen joined forces
with the KLH loudspeaker company, and together
they introduced the KLH 9. Due to the large size
of the KLH 9, it did not have as many sonic
limitations as the Quad. The KLH 9 could play
markedly louder and lower in frequency than the
Quad EM-
ESL
. Thus a rivalry was born.
Janszen continued to develop electrostatic designs.
He was instrumental in the design of the Koss
Model One, the Acoustech and the Dennesen
speakers. Roger West, the chief designer of the
Janszen Corporation, became the president of
Sound Lab. When Janszen Corporation was sold,
the RTR loudspeaker company bought half of
the production tooling. This tooling was used to
make the electrostatic panels for the Servostatic,
a hybrid electrostatic system that was Infinity’s first
speaker product. Other companies soon followed;
each with their own unique applications of
the technology. These include Acoustat,
Audiostatic, Beveridge, Dayton Wright, Sound
Lab and Stax, to name a few.
Electrostatic speakers have progressed and
prospered because they actually do what Peter
Walker claimed they would. The limitations and
problems experienced in the past were not inherent
to the electrostatic concept. They were related to
the applications of these concepts.
Today, these limitations have been resolved.
Advancements in materials due to the U.S. space
program give designers the ability to harness the
superiority of the electrostatic principle. Today’s
electrostats use advanced insulation techniques or
provide protection circuitry. The poor dispersion
properties of early models have been addressed
by using delay lines, acoustical lenses, multiple
panel arrays or, as in our own products, by
curving the diaphragm. Power handling and
sensitivity have also been increased.
These developments allow the consumer the
opportunity to own the highest performance
loudspeaker products ever built. It’s too bad Rice
and Kellogg were never able to see just how far
the technology would be taken.
f
requently
a
sked
q
uestIons
How do I clean my speakers?
Use a dust free cloth or a soft brush to remove the
dust from your speakers. We also recommend
a specialty cloth (available at the Xtatic shop at
www.martinlogan.com) that cleans your speakers
better than anything else we have tried. For the
wood surfaces it is acceptable to slightly dampen
the cloth.
Do not spray any kind of cleaning
agent on or in close proximity to the electrostatic
element. Avoid the use of ammonia based
products or silicone oil on the wood parts.
What is the advantage of EM-ESL?
Since the diaphragm is uniformly driven over its
entire surface—unlike a tweeter that is only driven
at its edges— it is the only technology that can be
