The Electrostatic Loudspeaker Design Cookbook

An encyclopedic exploration of the important issues, tradeoffs, and technical questions involved in building these fascinating speakers. Offers construction advice for both flat and curved panels. Includes a curved cell design by Barry McClune. THE ELECTROSTATIC LOUDSPEAKER has intrigued music lovers since their first commercial introduction just after World War II. Hearing music via such a device often turns ordinary music listeners into dedicated, passionate partisans of this transducer format as the only true path to accurate sound reproduction. Add to this the additional incentive that such speakers can be constructed out of readily available materials, and the convert turns into a devotee ready to invest quantities of time and energy into the nearest equivalent of the perfect loudspeaker. The ability to move a panel of graphite-impregnated plastic immersed in a high-voltage field with an audio signal has fascinated audiophiles since the earliest days of high quality sound reproduction after World War II. This enthusiasm leads inevitably into explorations of the legendary output transformer-less amplifier (OTL) genre since such devices match their high impedance outputs ideally to the elec-trostatic’s input. Then there is the electrostatic headphone sideshow which beckons tantalizingly. No one writing about the electrostatic has contributed more to the success of amateur electrostatic speaker builders than Roger R. Sanders. His first article on the topic appeared in The Audio Amateur in 1975 (pp. 18–28). His designs were inspired to some extent, and informed by, the pioneering work of David Hermeyer, who published a series of Audio Amateur articles on building electrostatics, along with power amplifiers designed to drive them. Electrostatic speaker builders have strong opinions about ideal formats, stator structure, polarizing voltages, and many other details. In this book the author surveys all the alternatives and keeps clear about his own preferences, many of which are subjective. The Electrostatic Speaker Design Cookbook is a complete guide for the novice and the experienced builder to successfully build the unusual sound reproduction device. As always, any project in electronic design is a series of choices balanced between goals and limita-tions. Sanders does an outstanding job of exploring the compromises and tradeoffs required to reach a satisfying result. Roger Sanders not only builds electrostatic speakers, he builds and holds patents on a number of other devices, his unique bicycle pedal being only one of them. He is also an amateur astronomer and a frequent contributor to periodicals dedicated to that topic. His wide knowledge of manufacturing and fabricating techniques, as well as extensive “hands-on” experience in making many devices with his own hands, enriches this book in a nearly unique fashion. Sanders has founded an interest group for electrostatic enthusiasts with a worldwide membership. He also makes his address available in this volume for any who need help solving problems, finding mate-rials, or just friendly conversation about one of his favorite topics.