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14     Electrostatic Advantages
How can sound be reproduced by something that you are 
able to see through? Electrostatic energy makes this possible.
Where the world of traditional loudspeaker technology 
deals with cones, domes, diaphragms and ribbons that 
are moved with magnetism, the world of electrostatic 
loudspeakers deals with charged electrons attracting and 
repelling each other.
To fully understand the electrostatic concept, some back-
ground information will be helpful. Remember when you 
learned in a science or physics class that like charges repel 
each other and opposite charges attract each other? Well, 
this principle is the foundation of the electrostatic concept.
An electrostatic transducer consists of three pieces: stators, 
the diaphragm and spacers (see figure 14). The dia-
phragm is what actually moves to excite the air and create 
music. The stator’s job is to remain stationary, hence the 
word stator, and to provide a reference point for the mov-
ing diaphragm. The spacers provide the diaphragm with 
a fixed distance in which to move between the stators.
As your amplifier sends music signals to an electrostatic 
speaker, these signals are changed into two high-voltage 
signals that are equal in strength but opposite in polarity. 
These high voltage signals are then applied to the stators. 
The resulting electrostatic field, created by the opposing 
high voltage on the stators, works simultaneously with 
and against the diaphragm, consequently moving it back 
and forth, producing music. This technique is known as
push-pull operation and is a major contributor to the sonic 
purity of the electrostatic concept due to its exceptional 
linearity and low distortion. 
Since the diaphragm of an electrostatic speaker is uniform-
ly driven over its entire area, it can be extremely light and 
flexible. This allows it to be very responsive to transients, 
thus perfectly tracing the music signal. As a result, great 
delicacy, nuance and clarity is possible. When you look 
at the problems of traditional electromagnetic drivers, you 
can easily see why this is so beneficial. The cones and 
domes which are used in traditional electromagnetic driv-
ers cannot be driven uniformly because of their design. 
Cones are driven only at the apex. Domes are driven at 
their perimeter. As a result, the rest of the cone or dome
is just “along for the ride”. The very concept of these
drivers requires that the cone or dome be perfectly rigid, 
damped and massless. Unfortunately, these conditions are 
not available in our world today.
To make these cones and domes move, all electromag-
netic drivers must use voice coils wound on formers, spider 
assemblies, and surrounds to keep the cone or dome in 
position (see figure 15). These pieces, when combined 
with the high mass of the cone or dome materials used, 
make it an extremely complex unit with many weaknesses 
and potential for failure. These faults contribute to the high 
distortion products found in these drivers and is a tremen-
dous disadvantage when you are trying to change motion 
as quickly and as accurately as a loudspeaker must 
(40,000 times per second!).
E
LECTROSTATIC
 A
DVANTAGES
Figure 14. Cut away view of an electrostatic transducer. Notice the 
simplicity due to minimal parts usage.
Figure 15. Cut away view of a typical moving coil driver. Notice the 
complexity due to the high number of parts.