Electrostatic Speakers

In the early 1990's I began constructing electrostatic speaker cells, and I have continued off and on since then working with them. At first I mostly followed the instructions in Roger Sanders' articles on the subject [1]-[7], particularly reference [6] which covers ESL cell fabrication for a compact system. I believe these articles are still available for reading on Roger Sanders' website ; you should check them out if you are interested in building electrostatics.

However, since that time some new materials have become available which make ESL fabrication easier and more reliable, and I have picked up some tricks and insights that have helped me considerably with these speakers, some of which I present on this page.

First I should clarify some things. When I say ESL fabrication, I am really talking about hybrid electrostatic speaker systems, where the low end is covered by a conventional woofer; this considerably reduces the requirements on the electrostatic cells. Full-range electrostatic speakers are a whole other story. I have never attempted to build a full-range electrostatic, and frankly I have never been tempted to try; hybrid systems, if made correctly, sound good enough that I don't see the point of taking on the added difficulties inherent with full-range electrostatics. However, some audiophiles claim that full-range ESLs are superior, and I really can't argue with them since I have no experience in this area.

The other thing I wanted to point out is that the general method of ESL cell fabrication presented in Roger Sanders' articles, and which I expand upon here, is not the only way to make electrostatics. See for example a recent AudioXPress article by Charlie Mimbs [8], where he constructs his ESLs using double-sided sticky tape; Roger Sanders warned about this approach because some kinds of tape can "creep" over time, but it seems to have worked well in this case. This article also presents a method of tensioning the diaphragm using a mechanical stretcher, whereas I use heat shrinking exclusively for stretching the diaphragm. You can also read about these alternate approaches on Charlie Mimbs' website.

I start out with the same basic materials as in Roger Sanders' method; I use Lincaine perforated aluminum sheets in the Albras finish for the stators, and I use approximately 65 mils thick Lexan plastic spacers to separate the stators from the diaphragm. In the following I present some of the techniques and materials that differ from information in Sanders' articles, and I also discuss some other points that I feel are important to know concerning electrostatic speakers.

For more detailed information, please see my three-part AudioXPress article called "Experimenting With Electrostatic Speakers", starting in the September 2012 issue.

Please select from the following:


[1] Sanders, Roger R., "The Sanders Electrostatic Speaker", The Audio Amateur 4/1975.

[2] Sanders, Roger R., "An Electrostatic Speaker System Part I", Speaker Builder 2/1980.

[3] Sanders, Roger R., "An Electrostatic Speaker System Part II", Speaker Builder 3/1980.

[4] Sanders, Roger R., "An Electrostatic Speaker System Part III", Speaker Builder 4/1980.

[5] Sanders, Roger R., "A Compact Integrated Electrostatic/Transmission Line Part I", Speaker Builder 1/1990.

[6] Sanders, Roger R., "A Compact Integrated Electrostatic/Transmission Line Part II", Speaker Builder 2/1990.

[7] Sanders, Roger R., "A Compact Integrated Electrostatic/Transmission Line Part III", Speaker Builder 3/1990.

[8] Mimbs, Charlie, "Hybrid Electrostatic Loudspeakers Constructed with a Twist", AudioXPress April 2012.