Son of Zen — Nelson Pass / 1997

The Zen has proven to be a popular and enduring do-it-yourself amplifier. The design addresses the audiophile's enthusiasm for singleended amplification, but is even more interesting for its exploration of the performance available at the extremes of simplicity, having only a single gain device. Judging by the mail, more than a thousand of them have been constructed, not including a couple of commercial rip-offs. Incoming mail is an excellent barometer of interest and taste among the readers. Letters suggesting design improvements provide the direction and the excuse to proceed with the Son of Zen. It responds to the following common… More...

Arch Nemesis — Nelson Pass / 2010

A poster of Einstein once said, “Things should be made a simple as possible, but no simpler”. This can apply to audio amplifiers, but if they are evaluated subjectively, the simplicity thing can get a little of of hand. Of itself, minimalism exerts a strong aesthetic attraction, and there is a reasonable belief that fewer components in the signal path allows more information to get through with less coloration. If like me you are interested in understanding of how we hear distortions with our brains (instead of our meters), you might appreciate that simple circuits help isolate these phenomena. I… More...