built his first ESL
( ElectroStatic Loudspeaker)
in 1972. He quickly appreciated the superior performance that a massless electrostatic offered over conventional magnetic speakers with regards to low distortion, lack of resonances, and incredible detail. But their problems of limited output, inability to produce deep powerful bass, and unreliability have kept him busy improving them over the last 30+ years.
The result of this lifetime of work is that Sanders Sound Systems ESLs
are the only ones to have solved all the problems and limitations of ESL
s. Roger's "Ultrastat" panels will play at ear-bleeding levels, cannot be arced, do not use or need protective circuitry, are immune to humidity, dust, and dirt, and do not need or use dust covers. They can be driven by multi-thousand watt amplifiers without damage. They are more rugged than conventional magnetic drivers. They do not fail and are so robust that they come with a lifetime warranty.
A major part of his work was devoted to dealing with the issue of high frequency "beaming" in large, planar loudspeakers. To deal with this issue, he invented the free-standing, curved, electrostatic panel. This made it possible to widely-disperse the high frequencies from a large ESL
. He published this invention in Speaker Builder Magazine in 1980. The Martin Logan company adopted his technique in their ESL
Roger expected that his wide-dispersion, curved panels would perform better than narrow-dispersion, planar speakers. But he discovered that the curved panel was inferior to a planer one with respect to transient response, imaging, frequency response, speaker placement, and output. These problems caused by wide-dispersion speakers spraying their sound all over the room instead of being directed at the listener. As a result, in a wide-dispersion speaker, the listener hears the room with all its confused and delayed reflections instead of the superb sound available directly from a planar ESL
. Roger won't compromise the quality of the sound by using his wide-dispersion design, so he abandoned it in favor of planar ESL
s. The sound from his planar speakers are superior to all others with regard to transient response, 3-dimensional imaging, and frequency response.
Full-range, crossoverless ESL
s are widely believed to be the "holy grail" of loudspeakers. In theory, using a single drive to reproduce the entire audio range, without the problems introduced by crossovers, would be ideal. Roger has built many such speakers. But the laws of physics cannot be circumvented. A full-range ESL
simply cannot produce deep, powerful bass or have generally high output and full dynamic range.
Roger spent 17 years developing woofer systems that would blend seamlessly with a massless ESL
to produce outstanding bass and end the frustrating limitations of full-range ESL
s. His well-designed, hybrid systems are far superior to a full-range, crossoverless ESL
While building and selling full-range ESL
s is easier and less costly than a hybrid, Roger won't compromise . Therefore all Sanders speakers are hybrids.
Crossovers are a major limitation in conventional speakers. The passive crossovers typically used are seriously flawed and cannot be used if you want a speaker with the highest possible performance. Electronic crossovers and bi-amplified operation are far superior to passive crossover systems and are absolutely essential for spectacular speaker performance. Therefore, all Sanders' speakers come with electronic crossovers (your choice of analog or digital) and bi-amplification.
To eliminate the usual customer complaint about having to buy two amplifiers to operate bi-amped speakers, Sanders supplies a bass amplifier as part of each speaker system. The customer then only has to provide a single amplifier of his choice just as they would for any conventional speaker system.
These amplifiers are not cheap, underpowered, or Class D switching amplifiers. They are multi-hundred watt, Class AB amplifiers that are very expensive, offer the finest in performance, come in beautiful chassis, and will drive the speakers with full dynamic range at realistic, concert hall levels.
When a speaker system is put in a room, it will interact with the room and this will have adverse effects on the sound. Even a "perfect" speaker system will be degraded by the room. It therefore is essential for all speakers to be adjustable to compensate for room effects. The electronic crossovers used in Roger's speaker systems have extensive controls to allow the user to adjust the speaker to compensate for the flaws in his listening room.
This adjustability means that the user can make the speakers sound almost any way they wish. It is no longer necessary to be "stuck" with the particular sound of a room/speaker combination as is the case with conventional speakers. If you don't like what you hear with Sander's speakers, you can adjust them so that they sound the way you like.
In summary, Sanders' speakers use the finest technology and design possible. No compromise is made to either to reduce cost or sacrifice any aspect of speaker performance. The combination of electrostatic mids/highs, transmission line woofers, and fully adjustable electronic crossovers makes it possible finally to have a speaker system that can do it all without compromise.