Patent Review: Dual Coil Electrodynamic Transducer with Channels for Voice Coil Cooling

James Croft reviews a published design submitted on behalf of Harman International Industries on January 2017. The design details an important approach to solving the everlasting problems of heat generation that limits the power handling capacity and the distortion-free acoustic output capability of loudspeakers, as well as their efficiency as electroacoustical transducers. This article was originally published in Voice Coil, September 2018.​​​​​​​

Mike Klasco (Menlo Scientific) writes about "a very cool" concept from Soundmatters, the company's UPstage speaker design, a new speaker product category and the next trend from the people that invented the soundbar. The sophisticated engineering implemented by soundmatters into the UpStage compact high-performance audio system was also the launch platform for BDNC's high-power, flat glass woofer that uses a 0.2 mm glass diaphragm. This article also explains what manufacturers need to know about the BDNC glass diaphragm, high-excursion, ultra-low profile woofer technology.

Do you remember the Electro-Voice T35 Super Tweeter? This was a high-performance horn tweeter that even today has state-of-the-art wideband response, high sensitivity, and a history that spans over six decades! This trip down memory lane relates the story of the T35, with a look at not just the tweeters, but also the people behind these developments. This article was originally published in Voice Coil, April 2010.