audioXpress April 2015 is Now Available Online and in Print

February 28 2015, 04:04
The new edition from audioXpress is available, and there are many reasons to quickly get to it.

We start with an extended editorial about RadioShack and the consequences of the company’ recent filing for Chapter 11 bankruptcy protection. We decided to call some of our authors, contributors, and industry friends for their thoughts on what was great about RadioShack’s business and where the company failed. Read what they had to say on page 4 and page 65.

Our main cover article is an in-depth review of the Benchmark AHB2 Stereo Power Amplifier by Gary Galo. If you are interested in amplifiers, this review will clearly explain why you should listen to this one. Benchmark’s new AHB2 stereo power amplifier uses feed-forward error-correction technology patented by THX that virtually eliminates crossover distortion. Designed in response to the needs of high-resolution audio sources, each channel of the AHB2 actually has two amplifiers — the main bi-polar Class-AB amplifier for driving the loudspeakers, and a low-power error-correction amplifier with ultra-low distortion levels. Gary spent some time with it and explains all the reasons why he was impressed. Very impressed.

The other main topic is actually another serving from our series on Wireless Audio development platforms. In this issue, audioXpress examines the history of APT (the company) and CSR, the company who bought APT and currently licenses the aptX technology for some of the best Bluetooth products available. We also dive into the multiple audio solutions offered by CSR, making this company one of the market leaders in wireless audio.

In the fifth article in our multi-part quest for realistic recorded sound, Ron Tipton focuses on to ambisonics.
In our series on Nordic audio companies, Mike Klasco explores the evolution of Danish company K & K Development, its beginnings as an offshoot of Ortofon, and its modern-day test and measuring systems.
Our regular Headsets column by Mike Klasco and Steve Tatarunis discusses headphone drivers. For readers waiting for the second part of the “Headphone Testing” article we published last month, the authors clarify that article is coming. They simply felt they should finish the description of the basic elements, before moving on. Anyway, they offer another insightful read on the subject.

On Sound Control, Richard Honeycutt looks in detail at the ODEON acoustic measurement system, even though it is best known as a computer modeling system for acoustics and electroacoustics. As Richard explains, “the current version also contains a comprehensive measurement system. The advantage of this system being included with the modeling software is that measurement results can easily be compared with results predicted by modeling, since both are presented in the same format.”

If you like reading about speakers and like DIY projects, you will be happy to read the first of a two-part article by Thomas Perazella that describes the author’s efforts to recreate the true bass sound he once achieved in a former home. He provides a lot of shared knowledge on building subwoofers.

Another DIY project this month comes from Larry Cicchinelli, sharing with us how to build a very useful four-output “Wall Wart” replacement. It is a simple modular project, which, no doubt, will be appreciated by many.

And finally, our Hollow-State Electronics column by Richard Honeycutt discusses Classic Tube Power Amplifier Circuits, including the Heathkit W5M, Dynaco Mark II, and the McIntosh MC75. Coming in May is our highly anticipated Glass Audio Special issue.

As usual, your new issue of audioXpress is now available at
To become a member, visit
You can also buy a single printed issue at
related items