Best Power Conditioners

Bravo to Shunyata for designing a system that recognizes the fact that not everyone has the cash, space or the inclination to run dedicated lines into a listening room. Apartment dwellers take note. You’ll never look at power strips and AC power quite the same way again. The Venom Defender brings much of the technology and many of the sonic improvements of Shunyata’s expensive conditioners to a more affordable price. NG, 239

Used with a CD player, the aR2p—Audience’s compact, dual-outlet power conditioner and isolation device—enhanced soundstaging, dimensionality, and depth. The 12-outlet aR12p was also found to be extremely effective, capable of delivering significant improvements in bass definition and depth, overall resolution, and soundstage depth. 162, 179, 186, 235

The Audience forte V8 power strip gets right down to business with eight hospital-grade AC outlets, each wired separately with high-purity, 14AWG copper. Plus, the entire electric circuit has been treated cryogenically. The V8 performed impeccably, with no discernible losses, changes, or degradations versus wall outlets. If anything, backgrounds seemed quieter and low-level transparency more fully resolved. Bass response also firmed up and conveyed greater control. Soundstage dimensionality and ambience retrieval were enhanced, to boot. Impeccable in construction quality, virtually unbreakable, and not liable to break the bank, the V8 ships with the exceptional forte f3 powerChord. All in all, a no-brainer. NG, 311

Housed in a full-sized chassis and rated for 20 amps of continuous current, Shunyata’s Delta D6 delivers the juice to more demanding systems, including high-powered amplifiers. Its most noteworthy sonic achievement was an expansion of spatiality and increased ease of presentation. At the micro level, images were pocketed within halos of ambience upon the soundstage—a finely focused presentation with an almost eerie lack of noise and distortion. Equipped with top-notch features like electromagnetic breakers, Hubbell outlets, vibration-dampening materials, and cryogenic treatment, Shunyata’s latest is among its most successful yet. It makes an audio rig less about electronics and more about music. NG, 305

The Clarus Concerto is an unassuming, but well-made, rack-mountable module with a power switch and dimmer button on the front, and a clever and unique cable-support bar on the back that prevents the dreaded heavy-power-cable droop we all know and hate. The Concerto offers a total of eight outlets, separately specialized for high current, digital, and analog sources. Clarus’ five-tier approach to conditioning lowers the noise floor without restricting dynamics. Reviewer Matt Clott’s digital and analog sources benefited from what the Concerto provided: blacker backgrounds, more dynamics, and a cleaner canvas upon which to paint the music. MC, 306

All power conditioning products claim to do the same thing: lower the various current and ground noises generated by your power grid and the wiring in your house and system. The difference between the Niagara and most of its competitors is that the Niagara 5000 does this task demonstrably well, raising low-level resolution of detail and reducing background hash (making for a clearer, better-defined soundstage and more neutral timbre top to bottom) without choking off current delivery. With 12 outlets (four of which are high current), the Niagara 5000 is equipped to handle just about anything in your system—and to render audible improvements in every aspect of the stereo image. JV

This AC conditioner from Shunyata takes what had been the state of the art in AC conditioning to a new level. It is based on noise-isolation technology that Shunyata developed for medical imaging equipment. The sonic result is quieter backgrounds, which allow for resolution of the finest micro-details. These low-level cues are vital to a sense of timbral and spatial realism, which are the areas where the Denali excels. The 6000S v2 is a shelf version with six outlets. Now available in an improved (but unreviewed) v2 version. RH, 272

Shunyata’s new Everest 8000 is easily the company’s finest effort yet delivering an entirely unprecedented level of performance. This eight-outlet conditioner in a vertical truncated pyramid chassis benefits not just from Shunyata’s previous work on AC power for audio, but from technology developed by founder Caelin Gabriel for Shunyata’s sister company, Clear Image Scientific. The XC power cord that connects the Everest to your wall outlet is no less impressive. The soundstage opens up with greater space and depth, with more vivid and tangible images, along with far greater resolution of air and space around those images. RH’s reference. RH, 311

The 81-pound Niagara 7000 is the brainchild of AC design engineer Garth Powell, whom AudioQuest hired and essentially gave him two years and carte blanche to design a new power device from scratch. Powell says the Niagara 7000 is not a power conditioner; rather, it relies on dielectric-biased AC isolation transformers to reduce distortion without reducing current to any component, including amplifiers. Essentially, the Niagara seeks to create a power bank for your amps so that it doesn’t have to strain to grab voltage from the wall. The most immediate and salubrious effect of the Niagara was to offer a more controlled and refined performance. The treble is smoother and rounder with the Niagara. Overall, the Niagara is a fabulous piece of equipment that adds sheen and palpability to the music that are utterly addictive. JHb, 271

Audience’s aR12-T4 power conditioner represents a substantial improvement over its predecessors, so much so that it would be fair to say that it borders on an order of magnitude advance. This is a world-class device, deserving your full attention. Give one a listen—perhaps the 6- or 2-socket variety—but be prepared to buy it. If you are anything like GW, there is no chance it will come out of your system once it is in place! GW, 268

As a skeptic about power conditioners, JHb was pleasantly surprised by the improvements in imaging and dynamics rendered by the Synergistic Research PowerCell. Unlike many of its brethren, the PowerCell did not appear to limit current. Instead, it offers even blacker backgrounds and lowered grit and distortion. Particularly noteworthy were the smoother treble and improved suppleness of musical lines. As with all conditioners, however, auditioning the Synergistic in your own system is a must, as the quality of electricity varies markedly from home to home. JHb/JV, 287