![](https://cdn.xingosoftware.com/audioxpress/images/fetch/dpr_1,w_300,h_394,c_fit/https%3A%2F%2Faudioxpress.com%2Fassets%2Fupload%2Fimages%2F1%2F20170524142616_VC-Cover-201706-June.jpg)
In this edition, Mike Klasco (Menlo Scientific) focuses on new Earphone and Headphone Technology developments. As Klasco writes, “I spend many of my waking hours involved with headphone and earphone development. At the start of most of these projects, we ask ‘Everything has already been done. What else is there left to enhance the quality of the user experience?’ Of course, there are always new developments, and a few of the most recent significant ones include personalization, comfort, freedom from spurious rattles and resonance, and isolation from the outside world.” This is a report you don't want to miss.
And of course, in the best Voice Coil tradition, this edition features a complete Directory of Earphone and Headphone Manufacturers, compiled by Nora Wong (Menlo Scientific). The directory lists some of the key earphone and headphone companies that offer original equipment manufacturer (OEM) or original design manufacturer (ODM) work.
To complement the directory, Nora Wong prepared a valuable summary of Recommended Earphone and Headphone Shows, which any professional interested in this expanding market segment should know about. As Wong explains, “Headphones (and for this article that includes earphones) are the hottest category in audio gear and have their own shows, most targeted toward consumers but now there are also trade shows.”
This month's Acoustic Patents column, prepared by James Croft (Croft Acoustical), addresses a “Passive Radiator with Dynamically Adjustable Resonant Frequency,” recently awarded to Joseph F. Pinkerton (Austin, TX), on behalf of Clean Energy Labs, LLC. This important patent, describes an audio speaker having one or more passive radiators, and more specifically, an audio speaker having a passive radiator with dynamically adjustable resonant frequency. The audio speaker can dynamically adjust the resonant frequency of its passive radiator so that it lines up with the main bass note frequency (or frequencies) of a given song. Croft reviews the patent and compares it with previous attempts to achieve this useful development, with significant potential if its full capability is realized.
For this month’s Test Bench, Vance Dickason characterizes an Eminence N151M-8 1” throat ring radiator compression driver coupled with the Eminence STI1 90° × 40° constant directivity horn. The N151M-8 is the latest in a series of 1” throat 1.5” diameter voice coil compression drivers, and the first ring radiator type for Eminence. Notable features for the Eminence N151M-8 include a mylar diaphragm driven by a 1.5” voice coil wound on a polyimide former and cast aluminum body, neodymium ring magnet motor, and field-replaceable diaphragm.
![](https://cdn.xingosoftware.com/audioxpress/images/fetch/dpr_1,w_300,h_225,c_fit/https%3A%2F%2Faudioxpress.com%2Fassets%2Fupload%2Fimages%2F1%2F20170524142635_VC-Cover-201706-JuneFrontWeb.jpg)
crown.
All this, plus the usual news in Industry Watch, make the June 2017 edition of Voice Coil an issue not to be missed. If you already subscribe, go to - www.gotomyvcoil.com - to download it.
Voice Coil is free for industry professionals. To qualify for a free subscription to Voice Coil, or renew your subscription, just go here: audioxpress.com/page/Voice-Coil-Subscriber-Services.html.