Michael Fremer,

Stereophile 6/2017 

Shunyata Research's groundbreaking Hydra Denali D2000/T and D6000/T power conditioners

Shunyata Research’s Caelin Gabriel is one of a handful of developers of power- conditioning products whom I take 100% seriously. A few years ago, when I swapped out one of Shunyata’s Hydra Triton series of power conditioners for an upgraded version, I heard some improvements in the sound of my system, especially a reduction in transient “edginess.” When I then visited the factory, Gabriel showed me measurements of both models that confirmed what I’d heard, and why. At the 2015 Consumer Electronics Show, another of that handful of developers I take seriously, AudioQuest’s Garth Powell, who used to work for Furman Power, had a stack of power conditioners that he was comparing with AudioQuest’s Niagara 7000, which he’d designed. When he asked the crowd of audio writers which product in the stack they’d first like to compare with the Niagara 7000, it was unanimous: the Shunyata Hydra Triton. It has become the reference against which all other power conditioners are measured.

The ensuing demonstration shocked the assembled: Compared to the Niagara 7000 ($7995), the system powered by the original Hydra Triton ($4995) sounded closed-in, almost muffled. Yes, it filtered out the considerable crap of the Venetian Hotel’s power lines, but at the steep price of snuffing out transparency and highfrequency extension. I heard the same thing at home; and so, after many years of satisfied use of Shunyata products I defected to the AudioQuest Niagara 7000. (Note: I own all of my reference gear except the power conditioners, which are loaners.) Now from Shunyata comes the new Denali series of power conditioners, in intriguingly shaped cases and at far lower prices. They sent me two D2000/Ts ($3495 each), each with two AC outlets (one for each of my darTZeel monoblocks), and one larger, vertically configured D6000/T ($4995) with three outlet pairs, which I used for my line-level gear (though the D6000/T’s lowermost duplex outlet is claimed to be able to deliver unlimited current to the most powerful amps).

The D6000/T’s tall, narrow shape means that precious shelf space can be reserved for signal-bearing products, while its 50mm, vibration-damping stainless-steel footers obviate the need for placing it on a dedicated platform. To counter power-cord droop—which worsens with the height of the power outlet above the floor, and can cause a plug to fall out—Shunyata invented an ingenious cradle system that keeps plugs plugged in. Most important is what’s inside. There you’ll find new noise-reduction technology resulting from Shunyata’s work in the biomedical field. Clear Image Scientific (CIS), a sister company, markets a version of the Denali that, per Shunyata, has been well received in medical circles.


Shunyata specifies for the Denalis measured noise rejection of >60dB (500kHz–10MHz)—“more than three times the normal noise isolation common to most power conditioners.”
According to Shunyata, “power conditioners of all types, such as iso-transformers, chokes, coils, regenerators, even the AQ Niagara [my italics] units post a measured spec of noise isolation between –20 to 28dB at 1MHz.” But Shunyata doesn’t explain how noise at a frequency of 1MHz can affect the audioband (20Hz–20kHz).

The Denalis include Shunyata’s QR/BB technology (patent pending), to eliminate “the sense of dynamic compression often heard when an amplifier is connected to a power conditioner.” They claim that QR/ BB, which is not based on capacitors or inductors but is a “passive materials– based approach,” provides better dynamics than plugging components directly into the wall. Each pair of AC outlets incorporates noise-eliminating filters similar to those used in the Triton v1 and v2 models, but with a claimed wider bandwidth. These are designed to eliminate component-to-component interference by capturing and isolating the noise commonly generated by component power supplies. Also included is a smaller, more efficient version of Shunyata’s patented Noise Isolation Chamber, claimed to significantly reduce electromagnetic interference.


Shunyata claims that Caelin Gabriel’s new Kinetic Phase Inversion Process (KPIP) is “likely his greatest invention”—a metals-treatment process claimed to be able to produce, within days, a degree of break-in whose audible results would otherwise take years. “Right out of the box,” Shunyata claims, “KPIP treated products will sound better than the same product that was broken-[in] during normal use for two years.” They also claim that KPIP deals not just with burn-in but improves wire directionality. The Denali series includes other technology and construction techniques that you can learn more about at www.youtube.com/watch?v=H77ivPYVIvg

HEAD TO HEAD WITH THE AUDIOQUEST NIAGARA 7000: As Shunyata took direct aim at Audio- Quest’s Niagara 7000 power conditioner, I thought I’d compare them myself. But first, I replaced the two Niagara 7000s (one for line-level gear, one for power amps) with the two Denali D2000/Ts and one Denali D6000/T Shunyata had sent and just listened. Given the demo at CES 2015 mentioned above, if the sound was now more open than through the Niagara 7000s, that would represent a major improvement.

And that’s what I heard: The sound through the Denalis was more open and brighter than through the Niagaras. It also seemed more exuberant, and punchier.

When I then unplugged the amps from the two Denali 2000/Ts and plugged them directly into the wall, the sound became coarser and less organized. So back those plugs went, into the Denalis. I recorded at 24/96 “That Happy Feeling,” by Bert Kaempfert and His Orchestra, from a four-song EP produced from the master tapes in 2004 by the German audio magazine Image Hifi (12" 45rpm, Imagehifi 007). No CD could ever sound like this.

Then, with the Niagaras back in the system, I recorded the track again. I now had two needle drops of the same cut, the only difference being the power conditioner into which the frontend— the phono preamp, preamp, A/D converter, etc.—was plugged when I recorded each.

Repeated plays of this feel-good, audio-porn sonic spectacular easily demonstrated the differences: “That Happy Feeling” begins with flute and xylophone in the right channel, and drum-kit brushes behind a centered kick drum. After a few bars, what sounds like a twangy, muted Fender Telecaster enters in the left channel. Following this intro, as the main melody begins, a strummed guitar appears in the left channel, as well as a somewhat boomy bass guitar.

The Shunyatas’ version produced somewhat brighter brushes but with less definition of transients, a bigger but sloppier-sounding kick drum with less-well-defined attacks, longer sustains, and longer but less tidy decays. The bass guitar was less well controlled than through the Niagaras—it seemed to keep going when it should have stopped. The strings, when they entered, had more metallic sizzle. Same with the trumpet, flugelhorn, and handclaps (which had a slightly metallic, processed quality through both sets of power conditioners).

“That Happy Feeling” was louder through the Shunyatas. Was this wider dynamics or less? Was the top-end sizzle and the rest of what I heard through the Shunyatas what’s actually on the record but was suppressed by the Niagaras? Or were the Shunyatas— in addition to their excellent suppression of the noise that was clearly audible when I plugged the amps directly into the wall—producing new artefacts of their own?

I don’t know. However, I can say without reservation that, compared to what I remember of the sound of Shunyata’s Hydra Triton v2 power conditioners, their new Denali models produced a far more open sound against super-“black” backgrounds.

As with comparisons of loudspeakers, I’d be careful about jumping to any conclusions based on a quick A/B. But after Wilson Audio’s Alexx speakers had been installed, for the listening for my review of them in last month’s issue, I ran a quick A/B of the AudioQuest Niagara 7000s and Shunyata Denalis at the power-amp end. Generally, I heard what I’ve described in these longer, more detailed comparisons.