Final Inverter Brochure

WHITE PAPER

Final Inverter Technology™
for Electrostatic Speakers

Final Sound Solutions

INTRODUCTION

Electrostatic speaker systems have been considered the absolute state of the art in
audio reproduction since the 1960’s, when the legendary KLH 9 first made its
debut. Shortly after, Infinity Systems introduced the Servo Static One, a full range
electrostatic design that was considered the best speaker of all time and led to
Infinity’s current position as one of the leading speaker brands in the world. In the
early 1990’s, Martin Logan popularized the concept of “hybridization”, the process
of blending dynamic and electrostatic technologies to achieve a higher level of
performance in a smaller physical space. These “integrated” hybrids achieved high
levels of sales when they became sleek and sexy instead of big and boxy

Electrostatic speakers are known for there clarity and transparency of sound, as well
for the very low distortion because amongst others the very low mass of the moving
diaphragm. Besides the very high sound quality, traditional electrostatic speakers
had also a number of principal disadvantages such as a very low impedance as
soon as the frequency goes above 1000hz even as low as one Ohm by 20000hz
(need for expensive and powerful amplifiers). Another known disadvantage for
traditional electrostatic speakers is the beamy pattern of the sound distribution
resulting in a narrow spot of the listening place. Because of the very principle of the
sound reproduction, electrostatic speakers need very large surfaces to reproduce
Bass tones (expensive)

Final loudspeaker systems are equipped with electrostatic transducers. The
electrostatic principle is based on the fact that two objects possessing a positive

charge will experience a repulsive force and a positive and a negative charged
object show an attractive force.

In case of electrostatic loudspeaker elements a thin Mylar® film, permanently
charged by means of a high voltage unit, is suspended between two perforated
plates. In case of the traditional Electrostatic speaker, the audio signal from the
amplifier is transformed in to a high voltage by means of an audio transformer and
delivered to the perforated plates as an alternating current.

The alternating electrical field caused by the two perforated plates (the stators) will
push and pull the film (the membrane). The membrane itself will move the air and
therefore produce sound waves.

Although the electrostatic principle is fairly simple there are a lot of problems to
solve. For instance we are dealing with a high voltage system so advanced
insulation technologies are necessary. On the other hand the design of the audio
transformer is crucial for the sound quality of the loudspeaker.

THE FINAL SOUND INVERTER’S UNIQUE SELLING POINTS

 Ultra Low distortion

 Transparency and life-like sound

 High-definition sound (a lot of detail)

 High Impedance resulting in lower power and lower-cost amplifiers

 Broad Stereo Image

 Excellent sensitivity on normal listening distance

 Much less affected by room reflections (against walls, ceiling and floor)

resulting in a lower-cost for the Home Theatre Installation.

 The Inverter principle results in a high degree of safety allowing the design

to comply with the UL and CE requirements

 The Inverter also needs smaller electronics, resulting in a flat and digital

lifestyle design.

Final Sound Solutions modular design allows applying manufacturing technologies
that allow for much lower manufacturing cost prices and as such more attractive
end-user prices.

THE INVERTER: THE FINAL SOUND SOLUTION

Final Sound developed the Inverter Electrostat over the last two years in
order to solve a number of the disadvantages of electrostats while keeping
the benefits.

Diaphragm

Stator plates

Additionally FSS has improved the diaphragm technology substantially, so it will
last much longer than traditional electrostats.