MartinLogan Monolith loudspeaker The Full-Range Electrostatic: Pros & Cons
The main inherent advantage of the fullrange electrostatic speaker system is that it allows a single diaphragm to embody the conflicting attributes needed for optimal performance at both extremes of the audio range. Its thin-membrane diaphragm can be made exceedingly light, for superb transient response and extended HF response, yet it can be about as large in area as desired, for extended LF response. And since that diaphragm is driven uniformly over its entire surface, instead of from a relatively small voice-coil, it circumvents the inherent problem of dynamics in requiring that a large area be driven from a small area (the central voice-coil). The electrostatic's diaphragm does not require the element of rigidity in order to move uniformly over its entire surface. And because the same diaphragm handles both bass and treb1e, the electrostatic does not need a crossover, with its inherent phasing and audible discontinulty problems.
These are the reasons why designers have persevered for over 40 years in refining the electrostatic, despite its unenviable history of woes ranging from gross inefficiency through "difficult" amplifier loading to daunting unreliability. Unlike dynamic speakers, which will handle momentary overloads with aplomb, most electrostatics will break down instantly the first time an overload hits them. The usual result—a small hole in the diaphragm—then becomes a point of vulnerability, which will from then on arc over at signal levels well below what the speaker could normally handle.—J. Gordon Holt