Shunyata Research AC Power-Conditioning System

Is a power cord the “Last Four Feet” in AC power delivery or the “First Four Feet”?

Long after I’d discovered through my own listening experience that signal interconnects and loudspeaker cables are important to good sound, I resisted the idea that power cords could affect sound quality. Think of the miles of transmission wires between the power generator and your home, and of the dozens or hundreds of feet of Romex in your house wiring, and then ask how a few feet of exotic AC cable at the end of that long chain can make one whit of sonic difference.

But as with all things audio, the proof is in the listening. In 1989, a visiting amplifier designer and I were auditioning two amplifiers, and after about an hour of comparisons he casually switched the two amplifiers’ power cords. Sonic characteristics that I had attributed to Amplifier A suddenly appeared in Amplifier B. I was listening to the difference in power cords.

The idea that a power cord comes at the end of a very long power-transmission system is purely one of perspective. From the amplifier’s point of view the power cord is the first few feet of the power-deliver system. You can almost consider the power cord an extension of the power transformer’s primary windings. And if you think of an audio system’s AC connections as a local network that begins at your wall outlet, the notion that AC cables can make an audible difference no longer seems so far-fetched. As for power conditioners, there’s never been a debate; individually filtered AC outlets prevent noise generated by one component from getting into another component through the AC connection, improving sound quality (assuming an ideally designed conditioner).

Whether or not there’s a theoretical basis for an audio phenomenon, there’s no denying the truth of a thorough listening experience. And that is a test the AC products from Shunyata Research passed—with jaw-dropping effect.

I went full-bore, replacing, all at once, an entire system’s worth of stock or aftermarket AC cords with the Shunyata Hydra 8 conditioner on the front-end components, a Hydra 2 on each power amplifier, and Shunyata Anaconda and Python Powersnake AC cables throughout. Even before products had settled in, the transformation of my system was unmistakable.

Think of flying at night over a city when there’s a thin layer of fog or mist beneath you. You see the lights below, but they’re slightly diffused and out of focus. The mist tends to scatter the light, reducing the contrast between the lights and the black background as the mist takes on a faint glow. Now think of flying over a city in the bone-dry Southwest on a perfectly clear and pitchblack night. The lights are vivid and distinct pinpoints cast against a coalblack background. You can easily discern— without trying—tiny details in the lights’ sizes, shapes, and hues. The view takes on an almost crystalline quality in its razor-sharp vividness.

That’s the effect the Shunyata products had on the musical presentation. I heard a huge increase in transparency— the magnitude of which was easily the equal of replacing a fairly veiled midgrade preamp with a world-class unit. The term “clarity” is seldom used in audio criticism, perhaps because it’s rather plain. But clarity is the best single word to describe the Shunyata’s effect on my system’s sound. This clarity was manifested as a sense of nothing between me and the music, of soundstage transparency, of precise spatial definition, and of instrumental timbre purity.

A closer look at how the Shunyata products affected the soundstage showed that instruments within the acoustic became tightly and precisely defined, and the sense of air around those images became more palpable. The delineation between the image and surrounding air was sharper, fostering a greater impression of hearing an actual instrument in an acoustic space. Concomitantly, the Shunyata system allowed my system to better express what Jonathan Valin calls “action”—the sense of bloom around an instrument expanding dynamically with its volume of sound. With more sharply defined image boundaries, and a more palpable sense of transparent air around those images, a greater sense of “action” was resolved. Consequently, music sounded more natural and organic, and less like a synthetic re-creation. A vivid example of “action” is the trombone solo on “Soft Winds” from the spectacular Keith Johnson recording From the Age of Swing by Dick Hyman [Reference Recordings].

Related to this phenomenon was a heightened ability to hear very quiet sounds, usually toward the soundstage rear, even in the presence of louder instruments. The result was a deeper involvement in complex music as each voice in the tapestry remained clearly audible. Hearing familiar music in this new light gave me an even greater appreciation for the compositions and arrangements. Two salient examples are the Ensemble Modern’s masterful playing on Zappa’s The Yellow Shark, and the fascinating, M.C. Escher-like pieces on Philip Glass’ soundtrack to Powaqatsi [Barking Pumpkin and Nonesuch, respectively]. The Shunyata products gave me new insights into these compositions and performances by making more vivid the interplay between instrumental voices. I could hear deeper into the music by virtue of the system’s higher sonic resolution.