The Latest Technology Updates and Smart Designs in audioXpress June 2019

May 9 2019, 09:15

Highlighted in our June 2019 edition is our feature article on Working with USB-C, What Audio Developers Need to Know. This Market Update details what every electronics designer needs to know about the updated USB specifications and ongoing product certification process, covering USB implementations up to USB 3.2 and explaining the context for the forthcoming USB4 update. With direct input from the USB Implementers Forum (USB-IF), audioXpress traces the evolution of the new USB Type-C standard connector, the new USB Power Delivery 3.0 specification, the recent certification program for USB Fast Chargers and supported Programmable Power Supply (PPS). 

These updates have consolidated technology in a big way, allowing for the development of more efficient devices, and we are certain all audio product designers will benefit from reading this comprehensive Market Update. As we remind readers in this edition’s editorial, it's time to ditch those mini and micro USB connectors!

Another highlight in our June 2019 edition, Ethan Winer explains how he designed and built the Null Tester! Now, what's a Null Tester? For years, many audiophiles and even some audio professionals have believed that signal wires can sound different. Obsessed with settling this dilemma, Winer designed a Null Tester device that compares any two signal wires and reveals their difference to a level below -110 dB. As he explains, "The beauty of a null test is that it's absolute, and reveals all the differences, including frequency response, noise, distortion, phase shift, and every possible artifact whether known or unknown." After a long research effort and two iterations, the Null Tester is working and is now fully explained in a dedicated article for audioXpress.

Also this month, there is a great DIY speaker project from George Ntanavaras, about the Sigma 100 Satellite/Subwoofer Loudspeaker System. In the first part of the two-part article, Ntanavaras shares his design for this loudspeaker system, a stereo loudspeaker system consisting of two satellite loudspeakers for the left and the right channel and one subwoofer common for both channels. The satellite loudspeaker is a two-way closed box loudspeaker with a 5” woofer and a 1” tweeter. With its small size it can easily integrate in every room, ideally placed on a stand with its tweeter axis aiming at the ears height of the listener. The subwoofer is a closed box with a 10’’ woofer driven by its own power amplifier. For the crossover between the satellites and the subwoofer, two different solutions were implemented — one using a miniDSP 4x10Hd versatile DSP and another using a pure analog active crossover with op-amps.

Also in this edition, completing some of the topics addressed from last month’s edition of audioXpress, Brian Lowe (Belleson LLC) continues his search for the Unicorn in the second (and final) part of "Measuring Voltage Regulator Ripple Rejection, this time focusing on the test fixtures. A must-read for anyone into audio electronics. Complementing the final article (which also includes some extra reading available in our Supplementary Material section online), Jan Didden, our technical editor, supplies an informative sidebar about super regulators to enhance the information provided by Brian Lowe in his main feature article.

This month, Bruce Brown concludes the “Restoration and Revival of the McIntosh MC 30" project, replacing the can cap on the top of the chassis, rewiring the rectifier tube socket, and explaining what you need to know about the wiring and much more, before doing the final checks and measurements.

For those readers who follow Richard Honeycutt’s Sound Control column, this month he explains “How to Work With an Acoustical Consultant,” because “Everyone knows” that, right? In this insightful writing, Honeycutt shares much of his own personal experience as an acoustical consultant and provides great advice for those in need of some professional help. As Honeycutt explains, “acoustics is a science and an art, and competence requires both formal training and experience. Those who have invested in the requisite preparation provide their services — for a fee — under the rubric of acoustical consultation.”

Also in this edition, Shannon Becker interviews Bradley Pfeifer, an experience designer, consultant and innovator who continues to push the envelope of technology, hoping to provide the audio industry with more organic, earth-friendly options. Pfeifer currently works as an outside sales development engineer with Nevada Assembly Service (NAS Electronics Manufacturing), a contract state-of-the-art factory located in North Las Vegas, specializing in “Made in USA” audio products manufacturing. And he has a few interesting ideas to share…

All this and much more, now available online, immediately, and on its way to those who subscribe to print.

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