R&D Stories: Getting Started with Automotive Audio Bus (Part 2)

The second article in a four-part series about Analog Devices' A2B or Automotive Audio Bus explores the technical underpinnings of the A2B bus design. Brewster LaMacchia examines how certain optimizations for automotive applications must be accounted for when targeting broader audio applications. He also includes a look at analog phantom power and how A2B provides that feature in a digital system. This article was originally published in audioXpress, November 2020.

This Voice Coil Spotlight article by Aminul Md Mehedi (Senior Application Development Engineer at Carpenter Technology Corp.) explains how the Carpenter-developed high-performance Hiperco 50 and Hiperco 27 soft magnetic alloys can contribute to better performing microspeakers and earphone drivers, improving "decibel (dB) density" in miniaturized consumer electronic devices. This article was originally published in Voice Coil, November 2020.

The driver under test in this Test bench is the SDx10 home audio woofer from Creative Sound Solutions (CSS) Audio, using XBL^2 dual gap motor technology licensed from inventor Dan Wiggins. The CSS SDx10 also has a well-appointed feature set that includes a very stiff coated black paper/carbon fiber blended composite cone with a convex black hard paper dust cap, NBR surround, and semi-progressive cloth spider. All this is driven by a (2.4" six-layer voice coil with two 12mm thick ferrite magnets sandwiched between a thick XBL-configured front plate and black-plated thick T-yoke. This article was originally published in Voice Coil, November 2020.

For this edition of Vance Dickason's Test Bench, the characterization centers on the brand new NERO-6MRN150D pro audio 6.5" midrange from SB Audience, the recently announced brand from Sinar Baja Electric (SB Acoustics). The new NERO-6MRN150D features a proprietary four-spoke-cast aluminum frame with efficient cooling, a curvilinear paper/graphite composite cone and large convex paper dust cap. The motor design combines a FEA-designed neodymium ring magnet and 49.5mm diameter voice coil wound with round CCAW on a non-conducting glass fiber former. This article was originally published in Voice Coil, November 2020.

In this Test & Measurement article from Dan Knighten (Audio Precision), the author focuses on the practical question of manufacturing test strategies and objectives and shares what measurements reveal about the device under test, offers suggestions for specific measurements, and provides techniques for various devices and scenarios. This article was originally published in audioXpress, November 2020.

In this review, Stuart Yaniger details his findings about the M23R Earthworks measurement microphone. The M23R is the latest omnidirectional model in Earthworks’ infinitely matched series of measurement microphones. It is designed to be an affordable reference solution, delivering an IEC 61672 Class 1 frequency response before applying any equalization. This article was originally published in audioXpress, November 2020.

Following up on the two Communication articles published in audioXpress October 2020, Hans W. Gierlich, from HEAD acoustics GmbH, a top expert in his field, contributed this great overview article. With most company employees working from home and the trend toward decentralized organizations and remote collaborations, where webinar and conferencing services are the new way of communication, this a timely topic. This article was originally published in audioXpress, November 2020.

November signals another anniversary for Voice Coil, the leading periodical for the loudspeaker industry. In this edition, Md Mehedi writes about how new Hiperco alloys can contribute to improved microspeakers, Mike Klasco discusses "This Year’s Crop of Measurement Microphones," followed by a directory on the topic. And in Test Bench, Vance Dickason characterizes the new NERO-6MRN150D pro audio midrange from SB Audience, and the SDx10 home audio woofer from CSS Audio. Access it online now!

To complement the extensive perspective of another Market Update feature article on DSP Products and Applications, published in the November 2020 edition, audioXpress was honored to have the valuable contribution from one of the main suppliers in the field. In this article, Youval Nachum, CEVA’s Senior Product Marketing Manager, writes about "The Evolution of Audio DSPs," discussing how DSP technology has evolved, its impact on the user experience, and what the future of DSP has in store for us.

This audioXpress November 2020 edition explores the latest trends in digital signal processing (DSP) and how it applies to all audio applications, now increasing in power thanks to cutting-edge artificial intelligence running on devices. In this issue, you will also learn how to "Test and Optimize Strategies for Conference Terminal Equipment," "What to Measure for Quality Control of Audio Devices," and more about Automotive Audio Bus A2B. Stuart Yaniger reviews the latest Earthworks M23R Measurement Microphone, and you can read articles about acoustics, audio electronics and the best in DIY audio from our monthly columnists.