Sound Lab electrostatic speakers incorporate a membrane having the lowest moving mass of any speaker technology. Furthermore, virtually every molecule of the membrane is driven identically. Is this important? Here’s the answer.
Bottom line: Spin-offs from space-age developments have provided materials to make ideal electrostatic speaker panels. Membrane materials are now available in thicknesses of just a few millionths of an inch.
Lowest mass: As a result of the above, one advantage of the electrostatic panel becomes apparent: it has the lowest moving mass of any acoustic transducer, even lower than the so-called mass-less “flame” speaker, whose ionic capsule has a higher equivalent mass. Or the ribbon speaker, whose membrane requires metallic elements to conduct relatively high current (hence, mass and heat).
The moving mass of the electrostatic speaker membrane is but a fraction of the air load that it is moving. And, since the membrane is not required to carry high current, heat is never a problem as it is in dynamic and ribbon speakers.
Conductive Coating: The thickness of the conductive coating required to store electrical charge on the membrane need only be a few molecules thick. As a consequence, inertial effects are virtually eliminated. The slew-rate of the membrane is faster than that of the human auditory system, resulting in fast detailed bass, natural mids and clear highs.
Membrane Damping: Another advantage of the low-mass membrane is that it’s motion is damped by the air it is driving. This eliminates the effects of resonance such as the cone breakup of dynamic speakers. The result is sound that is more natural, where transients are more detailed and crisp and where sustained sounds are sweeter, cleaner, and more believable.
Unique force connection: The second major advantage of the electrostatic panel is the manner in which the electrostatic force is coupled to the membrane.
Panel design: In designing the electrostatic panel the stator is made to have the same area as the membrane. This results in an even distribution of the driving force over the entirety of the membrane (iso-phasic force). In other words, every point on the membrane is driven independently, but identically.
Zero Stiffness: The evenly distributed force that moves the electrostatic membrane eliminates the need of the stiffness that’s required by cone speakers to control cone movement. Stiffness equates to increased mass, which equates to undesirable inertial effects, which equates to lack-luster sound.
Low mass, distributed force: No other means of moving air has such inherent control. Distortion products are greatly reduced, even at high sound levels. As stated in non-scientific jargon, there is no “cone breakup distortion” since there is no cone to “break-up”.
Finale: As a consequence the electrostatic speaker panel exhibits the lowest mass, lowest distortion and the tightest control over membrane motion of any type of transducer. This means that a properly designed electrostatic speaker re-creates music with unsurpassed accuracy and naturalness. That’s what Sound Lab is about.