You Can DIY! eDD - A Direct-Drive Amplifier for Electrostatic Speakers

This article details a lifetime project from audioXpress' technical editor Jan Didden. After a successful restoration project of a pair of precious ESL-63 Quad electrostatic speakers, he opted to design and build the eDD, a well-performing high voltage amplifier to directly drive electrostatic speakers. This challenging but successful DIY project with a design goal of 1500V RMS at 20mA RMS over the full audio band, took a while to complete but was a success. This article shares every step of the construction.

Truly reminding us of those large JBL and Urei speakers and studio monitors, but promising the subtle performance of a pair of Quad electrostatics, the Elypsis1512 loudspeakers, from British brand Stratton Acoustics is a very unusual proposition in current times. According to the company, the Elypsis1512 is a loudspeaker system with high efficiency and wide bandwidth, very low coloration and distortion, and "the ability to paint solid aural images."

UK-based PMC is celebrating its 30th anniversary this year, marking three decades of ‘Best of British’ loudspeaker design and manufacture for both the international professional music production and audiophile markets. From a modest start as two men in a garage to 30 years of the biggest movie soundtracks and albums in the world, the Professional Monitor Company Limited, had a remarkable trajectory grounded on a common devotion for transmission line designs and a fundamental belief in fidelity.

In its August 2020 edition, Voice Coil featured an article by experienced speaker designer Igor Levitsky, highly recognized in the industry for developing some of the best planar magnetic speaker and headphone drivers for some of the most reputed brands, focusing precisely on this type of technology. It seems clear that we will see more and more headphones and speakers using thin-film drivers, as the industry is now perfecting the use of different types of diaphragms and materials. The August 2020 edition of Voice Coil includes the first part of this article, completed in the September 2020 edition.

International Audio Group (IAG) announced further expansion with the appointment of industry veteran, Steve Hutt to Director of R&D - Wharfedale Pro. With more than 30 years in the professional audio business Steve chairs the AES standards and technical committees on loudspeakers, has authored numerous AES technical papers and holds 15 Patents.