Powerline Accessory Reviews

Listening
When the PerfectWave P10 Power Plant was feeding my entire system, based on DeVore Fidelity The Nine loudspeakers and including a Leben CS-600 amplifier and analog and digital sources, I experienced exceptional musical moments more often, finding myself sitting up and taking notice of some musical detail. Streaming the Tidal playlist "Wildwood Flower: Best New Folk and Americana" at CD resolution, I was startled by the creaminess of Dori Freeman's voice in "Where I Stood," from her eponymous first album (CD, Free Dirt DIRTCD 0074). The percussiveness of Kristin Fossheim's fortepiano was visceral in the first movement of Beethoven's Sonata for Cello and Piano 2 in G, Op.5 No.2, and Bjørn Solum's cello had a pleasant buzz (24-bit/96kHz download, 2L 79). When, on a low note (as at 2:32), the cello's body resonated strongly, the room shook; could this be the "better bass" that PS Audio says on its website that I should expect? Of course, the P10 doesn't get all the credit—it's on the recording, and it takes a whole system to reproduce it—but it was less impressive with my system plugged straight into the wall.

Similarly, in the opening measures of Johan Kvandal's Fantasy for Clarinet, Op.68 No.2, also on 2L (SACD/CD, 2L 55)—a Meridian Master Quality Authenticated recording played through a non-MQA DAC, which means, according to Meridian, that it should sound a bit better than a CD—the close-miked clarinet had exceptional body. And when an early, large crescendo challenged clarinetist Fredrik Fors's dynamic range, his sound broke up in a way that's familiar to me (I've heard that sound live, from good seats), but that rarely comes across from recordings—at least not with such humanity. The P10 consistently helped bring out music's varied textures so that I was more actively engaged in it. It was hard not to listen.

There's evidence that the quality of AC power is especially important in digital audio. In his review of AudioQuest's JitterBug USB noise filter ($49) in the September 2015 issue, JA related what happened when his computer broke and he began listening to CDs again with his Ayre Acoustics C-5xe^MP universal player: "Every disc I played sounded more solid, more corporeal than I remembered from the many times I'd played the same tracks from the Mac mini. The low frequencies sounded more authoritative, much as they had when I bought a Mark Levinson No.31 CD transport (now long since retired with mechanical problems)." With the JitterBug—a purely passive device that conditions a component's USB outputs—JA found that music from his Mac mini sounded much more like what he'd experienced with the Ayre: "The low frequencies acquired more of the authority I experience with CDs."

I heard the same thing in my home, with my system plugged into the P10: more authority in the low frequencies. JA's observation (and mine) illustrates the importance of power—the height of waveforms, not just their timing—for digital sources, which is where I've noticed the most improvement with the P10 (footnote 3). I've already mentioned the Power Plant's effect on music's textures, and the increased bass authority; with the P10 in the system, I also found that the aural images reproduced from digital sources—specifically, PS Audio's NuWave DSD, and their DirectStream DAC, which I borrowed from JA—were also fleshier, more corporeal, and better located in space. The sound with the P10 also seemed more natural and less electronic—almost suggesting a physical rather than electronic playback medium. As I wrote in the review of the NuWave DSD, a wood block sounded like a wood block, not a recording of a wood block.

Conclusions
In this age of improving power supplies, is a device like the PerfectWave P10 Power Plant necessary? That will depend on the quality of your incoming AC, something that varies from region to region (footnote 4). My apartment building is small by Manhattan standards—just 25 apartments—but it's attached to similar buildings on right and left, with another one just behind. Right now, my MacBook Pro detects 33 wireless networks. Then there are the dimmer switches, switching power supplies, and cheap electronic transformers attached to low-voltage lights. All of those things affect my power supply—and this summer, the more than 30 window air conditioners in my building will suck even more energy from my AC.

Even as I write this, in March—still in heating season!—the P10's built-in 'scope tells me that the power coming out of my wall has 4–5% total harmonic distortion. The result is a dejected-looking wave more sawtooth than sine: it looks as if it's about to break. To mix metaphors, its peaks are like erstwhile mountains in West Virginia coal country (speaking of decrepit power infrastructure). Again, the reason this happens is the reason it matters: The peak of the household-AC waveform corresponds to the point where the capacitors in the power supplies of my audio components recharge. Chop off that peak, and the power supplies in my gear are starved at least a little bit, even when the available power seems ample.

It's not surprising that such a dejected-looking sinewave could suck the joy out of music. I knew it was possible that fixing my power would make my music cleaner and more accurate. What I didn't anticipate was that it would make the music so much more engaging. Maybe more accurate is more engaging—an appealing thought. Anyway, the PerfectWave P10 Power Plant may be an essential accessory for any audiophile who lives in a neighborhood like mine. A power conditioner—sorry, regenerator—may not be a sexy purchase, but I'm going to have a hard time sending this thing back.

But, again—it depends. If you live in a quiet valley with a little stream running through it, and your house is served by its own private transformer, you may not need a power regenerator to get the kind of sound I'm getting with the P10. (I lived in a place like that for some 10 years; unfortunately, the acoustics sucked.) If you live in the US, PS Audio makes it easy to find out: You can audition a PerfectWave P10 Power Plant—or any of the other components for sale on their website—risk-free via PSA's home-trial program.

---

Footnote 3: About 10 minutes into a YouTube video, Ted Smith, who designed PS Audio's DirectStream DAC, points out that imprecision in the rail voltage has an effect very similar to that of clock imprecision in digital components—it causes a form of "jitter"—and the higher the frequencies a device operates at, the more critical that imprecision becomes.

Footnote 4: It's also true that some components can more easily overcome the problems created by degraded AC power, but without testing, it's impossible to know.