Willow Revisited: A Design Celebrating the Enthusiasm and the Creativity of the Builder

audioXpress December 2011 introduced readers to Willow, a “proof-of-concept” project featuring a PMBF4393 JFET and HA5002 buffered preamp, built as a companion to the author's 5002 power amp, and the first to use this typology. After considerable positive DIYer feedback, the Willow was revised and updated, and this article, Willow Revisited was published in February 2016.

In this high quality project, Robert Nance Dee designs a potentiometer for accuracy and flexibility. A pot with 64 levels and precision metal film resistors that is hard to beat for sound or facility, as he describes it. The project started with a clean sheet, looking to address potentiometer design with a quality that rivaled existing designs while maintaining a reasonable cost. This article was originally published in audioXpress, September 2011.

I built this amplifier to run my Dynaudio X12 speakers. The X12s are not known for efficiency, but these little mono blocks run the accurate X12s with ease. Don’t be fooled by their low power output. The limiting factor is voltage, not their ability to drive a load. This article was published originally in audioXpress, February 2012.

This project, originally published by audioXpress in December 2011, has been the topic of much discussion, updates and follow-up projects, so much so that we decided to make it available online. As the author, Robert Nance Dee, explains, “…the people who have listened to this amp can hear the difference. I built it as a companion to my 5002 power amp, both using the HA5002 buffer.”