How does it work?
The electrostatic loudspeaker is very simple in concept, but difficult to construct successfully in practice. lts operation relies on electrostatic attraction and repulsion, in much the same way as a piece of thin paper attracted to a rubber balloon that is charged by rubbing it against fabric.

The electrically charged ultra-thin conductive film diaphragm is tensioned and placed close between two metal grids. When a high voltage audio signal is applied to the metal grids, the diaphragm moves in response to the signal, moving towards the grid which at that instant is oppositely charged, and away from the grid which has the same charge as the diaphragm. The diaphragm responds in an essentially linear manner, producing sound waves which are a very accurate reproduction of the original sound.
Why is it better?
Imagine a normal speaker as a point source, from which the sound waves produced diffract at a great angle. This causes rapid decrease in volume and quality over a short distance.
Then imagine a flat electrostatic panel producing sound from the same input signal. This time the sound waves are produced over a large, flat area, therefore have very little diffraction and the volume decreases much less over the same distance.


Compare Speakers
HUMMINGBIRD II
Audio Quality
Frequency Response
5kHz-45kHz
Sensitivity (equivalent)
89dB/1W/1m
Impedance
Normal 4Ω
Crossover Frequency
8kHz/ 12kHz/ 16kHz
DC Input
11-15V/ 120mA
Amplifier Minimum
40W
Amplifier Recommended
60W
Physical Specifications
Dimension (cm)
ESL:6.8x2.2x34.5
Drivers
-
Weight
ESL:1.5kg