Barry Waldron (September 2000): Roger Sanders has been designing and building ESLs since the early 1970s. His design strategy mates ESL panel and Transmission Line woofer. He is the author of several ESL construction projects (see: "Speaker Builder" magazine and "The Audio Amateur Loudspeaker Projects" book.), and, the inventor of the free-standing curved electrostatic loudspeaker driver. He is best known as the author of 'The Electrostatic Loudspeaker Design Cookbook." This manual is the bible for the DIY ESL-builder. Buy and read it before starting your project.

This treatise is a definitive set of instructions, explanations and arguments for achieving the most realism possible; it will save you a lot of time and money. The book is written for the audiophile hobbyist, not the engineer. The information is easy to understand and presented in short paragraphs. DIY ESL support is provided by Barry Waldron and the ESL Information eXchange.

In 1997 Roger Sanders joined Rajan Varma and formed InnerSound, a company dedicated to bringing the finest audio products to the world-wide market, and providing a level of performance heretofore only enjoyed by a relatively few builders. The company's flagship speaker, "Eros", is hybrid ESL and Transmission Line woofer. The system includes an electronic crossover and 200 w/p/c bass amplifier. "Isis", is a smaller speaker of similar design that can be energized with a single amplifier.

InnerSound also has a line of electronics to compliment their speakers. Their first two purpose built products are the "ESL Amplifier"; and, matching preamplifier with separate phono stage. The power amplifier incorporates several unique features and is designed to deliver a tremendous amount of voltage and current to the difficult reactive loads presented by full-range and hybrid speakers. When driving magnetic speakers, the ESL amplifier will deliver over 300 w/p/c into an 8 ohm load, and over 600 w/p/c into a 4 ohm (or lower) load.

For more information go to (see also Commercial Electrostatic Loudspeakers, Innersound)


A Bibliography of Roger Sanders' Publications

  • The Sanders Electrostatic Loudspeaker, TAA April 1975, pp 18-28 (PDF, available on exchange basis)
  • The Sanders Electrostatic Amplifier, TAA Jan. 1976, pp 12-16 (PDF, available on exchange basis)
  • An Electrostatic Speaker System Part 1, Speaker Builder, Feb. 1980, pp 20-36
  • An Electrostatic Speaker System Part 2, Speaker Builder, March 1980, pp 20-27
  • An Electrostatic Speaker System Part 3, Speaker Builder, April 1980, pp 26-30
  • A Compact Integrated Electrostatic/Transmission Line Part 1, Speaker Builder, Jan. 1990, pp 30-38,66-67
  • A Compact Integrated Electrostatic/Transmission Line Part 2, Speaker Builder, Feb. 1990, pp 36-47,77
  • A Compact Integrated Electrostatic/Transmission Line Part 3, Speaker Builder, March 1990, pp 38-47
  • The Electrostatic Loudspeaker Design Cookbook, First Edition, 1995, by Roger Sanders with Barry McClune, Audio Amateur Publications Inc., P.O. Box 576, Peterborough, NH 03458-0576, +01 (603) 924-9464, ISBN: 1-882580-00-1. In the Netherlands this book can be obtained via: Clear Sound in Leeuwarden (+31 (0)58-159927). Price ± Fl 85, $42,-