New Ways to Measure Noise Cancelling, Transparency, and Other Modes in Headphones and Earphones

Now that headphones and earphones are adding situational awareness, hearing protection and hearing enhancement features, HEAD acoustics created new test methods to evaluate these functions, faithfully simulating environments that a consumer might typically encounter when using products with these features. As an experienced reviewer in this category, Brent Butterworth was invited to visit HEAD acoustics' US headquarters in Brighton, MI, to learn about all the solutions the company has developed for this purpose, based on measurement techniques outlined in ETSI standards.

audioXpress December 2023 includes a market overview of multiroom audio, Brent Butterworth writes about new ways to measure ANC earbuds, and Stuart Yaniger measured the new Axign and GaN Systems Class-D audio amplifier board. Richard Honeycutt writes about tubes, BJTs, JFETs, MOSFETs, and ICs, and Dimitri Danyuk, discusses JFETs in audio circuits. Douglas Self explains how to optimize variable-frequency tone controls, and Jan Didden shares his eDD direct-drive amplifier project.

In this valuable review for product developers, Brent Butterworth shares what he learned about two evaluation solutions intended for designers of true wireless earbuds, the fastest growing product category in the audio industry. With this reference design and developer kit, Knowles made it easier for companies to add sophisticated true wireless earphones to their lines — whether they develop their own design or adopt one that’s ready to go. audioXpress tried out both options.

audioXpress September 2023 is a rich issue in the amount of audio topics explored and depth of analysis. Learn about the latest sound meters and acoustical simulation tools, what immersive audio really is, and what is possible with the development kits for true wireless earbuds from Knowles. Roger Shively does a full analysis of the Dinaburg C2S Concentric Coplanar Stabilizer speaker technology, Charlie Laub explains how to build a Minimally Baffled Dipole Loudspeaker, and Gary Gesellchen reveals viable bass reflex speaker designs.

Great articles, practical projects, reviews, and audio technology previews start the year in full force! That's what our readers will find in audioXpress January 2022, starting with an update on new materials and engineering approaches for loudspeakers, and articles by Charlie Hughes, Scott Dorsey, Frans de Wit, Ken Bird and Mike Harkins. Brent Butterworth reviews the Olive Pro earbuds, while Raj Senguttuvan from Knowles discusses differentiation for True Wireless Stereo (TWS) design and development.