audioXpress - June 2017

FEATURES
12 Even’s EarPrint Technology
Precision Listening for Earphones and Headphones
By Mike Klasco and Alex Vlach
Learn how Even is reinventing personal audio with technology that tunes sound to each listener’s unique hearing with its patent-pending Even EarPrint process.

18 Head Space - A Binaural Recording Session
By Neville Roberts
New developments in binaural recording have inspired UK-based record label Chasing The Dragon to start producing binaural recordings alongside its conventional recordings. The company recently conducted a unique experiment to compare it against more conventional recording techniques.

32 Current Feedback and Voltage Feedback Fallacies
By Michael Kiwanuka
This author relies on math and science to prove his assertion that the classifications for current feedback and voltage feedback are inaccurate.

38 A “Sources 101” Update
By Walt Jung
This article revisits the author’s “Sources 101” article, originally published in audioXpress in April and May 2007, as well as several follow-on letters, available online on the audioXpress website.

52 Cherry Bomb—A VFET SET Amplifier (Part 1)
The Concept, the Design, and the Plan Modifications
By Thomas Perazella
This audio enthusiast embarked on an epic build after discovering a rare Yamaha 2SK77 VFET transistor in his parts bin.

COLUMNS
IT’S ABOUT THE SOUND
8 Loudness Revisited (Part 1)
It All Started with Volume Control
By Ron Tipton

SOUND CONTROL
26 Assessing Audio Quality Using the MATT Test
By Richard Honeycutt

QUESTIONS & ANSWERS
46 Music Takes Flight with Raven Audio Sound Systems
An Interview with Dave Thomson, CEO of Raven Audio
By Shannon Becker

HOLLOW-STATE ELECTRONICS
58 A Range of Power Supplies for Hollow-State Guitar Amplifiers
By Richard Honeycutt