Distortion Meter and Audio Interconnect Tester

In this article for audioxpress, Ed Simon writes: "There seems to be controversy over what testing means in audio. Measuring a difference does not mean you can hear it. On the other hand, if my ears tell me there is a difference between two audio chains and I cannot measure it, that does not mean it is not there. Probably, I'm just using the wrong method to determine audio differences." And after trying to measure all sorts of things to compare which ones sounded fine - or not - he decided the next step would be to build a dedicated more sensitive measurement. This article was originally published in audioXpress, November 2009.

The April 2020 edition of audioXpress is now available and features two essential Market Updates, one focusing on the industry transition to active headphone and earphone designs, and another on how to leverage the latest voice capture and processing technologies. The issue also explains how to evaluate listening effort, and Stuart Yaniger puts the Linear Audio Autoranger Mk II Interface to the test, while Ed Simon writes about AC Power Rectification. Another issue to read and use as reference.

audioXpress March 2020 focuses on Audio Test & Measurement. In this edition, learn how to find the right Test & Measurement solution, learn more about how to optimize audio production tests, and read the review of the new Dayton Audio DATS V3 Test System. Luke McCready also reviews the fantastic Audeze Mobius planar magnetic, wireless headphones. There's plenty more to read and learn about in our regular columns Sound Control and Audio Scope, plus a new article from Ed Simon on Powering Audio Circuits.

This year we thought our readers would like to know which of the topics and stories published online in 2017 were the most popular for our community. We looked at the most-read articles of 2017 in audioXpress.com (which also includes selected articles from Voice Coil magazine), and we created this Top 10 list of news stories and online articles. Here are the results!

This project is based on a previous audioXpress article: “A Solid-State Single-Ended Power Amp” by Ed Simon, published in the April 2006 issue. Ron Tipton was deeply impressed with this amplifier project which used only five transistors per channel, two of them being current sources. This article was originally published in the old audioXpress website as a PDF, but was never reposted. Now we make available online with updated references and links.

In this simple amplifier project, Ed Simon describes a Class-A amplifier design that mainly intends to reproduce music with reinforced emotional expression. That's what you normally get with a quality design, but to achieve it, the author shares the complete concept, power requirements, circuit topology, construction and testing of this single-ended amp... in a solid-state design. This article was originally published in audioXpress, April 2006.