Since the 1980s, I’ve been asking every speaker designer I meet, “What amplifier do you recommend using with your speakers?” Annoyingly, they always say, “My speakers are easy to drive. Any amp will do.” Whereupon I’d whine, “Aww, come on man, don’t feed me that. What amp did you use when you were designing the speaker?” The closest any manufacturer came to providing a real answer was Wendell Diller of Magnepan, who, when I reviewed his .7 quasi-ribbon speaker, said, “We used an amp of our own design. It’s not for sale. But any amp that doubles its power into 4 ohms will be fine.” Wendell’s answer helped me choose effective amplification and feel more confident about my conclusions.
Unlike loudspeaker manufacturers, headphone manufacturers know that which amp a reviewer uses could make or break a review of their product. So, wisely, they seem grateful when I ask for guidance.
When I reviewed Dan Clark’s flagship Stealth planar-magnetic headphone in Gramophone Dreams #62,1 I asked Clark Audio’s president, Andy Regan, if he would “please” recommend an amp that he thought would allow the Stealth to perform at its full potential. In response, he sent me HeadAmp’s $1995 GS-X Mini headphone amplifier/preamp. This popular, drives-everything headphone amplifier allowed the Stealth and every other headphone I’ve run through it to reproduce recordings with a grainless, easy-flowing dynamic that makes vocal recordings sound exceptionally natural. Because it is more powerful (6W into 25 ohms, 4W into 50 ohms, 2W into 100 ohms) than the amps described below, I used the GS-X Mini as a reference during the course of this report.
When I review state-of-the-art electrostatic headphones, Woo Audio proprietor Jack Wu loans me his divine $8999 parallel, single-ended 300B 3ES electrostatic amplifier/preamp. For all other types of headphone reviewing, and for daily use, I rely on Linear Tube Audio’s uniquely wonderful Z10e, a full-function tube integrated amp that, in addition to powering magnetic headphones, drives electrostatic earspeakers my reference loudspeakers. Ever since I first raved about it in Gramophone Dreams #36, the $6950 Z10e, which is
