Robert Deutsch

Audio show exhibitors have a lot of obstacles to contend with: equipment not showing up or showing up damaged, problem with room acoustics, problems with the electrical supply, equipment malfunctioning just as the show starts, and countless others. Ian Grant of Grant Fidelity told me that when he first set up his turntable front end it was picking up the signal from a local radio station! Being an ingenious engineering-type, he located the source of the interference (he could see the station's antenna from the hotel window), and got some building insulation material that had aluminum foil as part of its construction, and taped it to the hotel window. Voilà! Problem solved!

In the November 2018 issue of Stereophile, Jim Austin reviewed PS Audio's DirectStream Power Plant P20 AC regenerator ($9999). PS Audio had sent me the less expensive DirectStream Power Plant 12 ($4999), hence this review.

Why use an AC regenerator rather than plugging components straight into the wall?

PS Audio's first product, back in 1973, was a standalone phono stage; more recently, their PCA-2 preamp had an optional phono board. The GCC-100 integrated amplifier that I review this month has no room inside for a phono board, so they've gone back to producing a separate phono stage: the GCPH ($995). Like the other products in PS Audio's current line, this one is based on the Gain Cell, one module on the input side connecting to the cartridge, followed by a passive RIAA curve (with a claimed accuracy of 0.1dB over the 40dB range of the curve), and another Gain Cell on the output side.

Determining whether an idea is brilliant or off the wall is often a matter of perspective—and of looking at the results that follow from the idea. Take the notion of AC regeneration. AC is what comes from the wall socket, courtesy a network of power-generation plants, and it's specified as having a certain voltage and frequency, with the amount of current limited by fuses or circuit breakers in the electrical panel of the house or apartment. Audio components—other than those powered by batteries—are designed to convert this alternating current (AC) to direct current (DC), then produce variable AC that drives the speakers to produce a facsimile of that signal. In short, AC provides the raw material used by audio components to do their job.