November 2005 Reviewed by Anthony Di Marco	Balanced Power Technologies BP-10.5 Signature Plus Power Conditioner

Description Model: BP-10.5 Signature Plus Price: $2999 USD Dimensions: 13"W x 6.5"H x 14"D Weight: 75 pounds Warranty: Three years parts and labor Features Custom toroidal transformers Balanced, high common-mode-rejection AC output Four stages of EMI/RFI filtration Copper-foil laminate between primary and secondary windings Carling magnetic circuit breaker Hubbell 20A-rated, GFCI-protected, cryogenically treated industrial duplex outlets (ten outlets total) Iso-Cones

Features (cont'd) Multiple layers of grain-oriented steel laminated around the transformer circumference Separate noise filters on each duplex outlet Three-layer chassis damping Heavily damped black powder-coat aluminum chassis Surge protection and current-overload protection Non-magnetic brass and bronze hardware High-current four-stage filtering 0.25"-thick machined-aluminum faceplate available in silver or black Polypropylene 250VAC audiophile-grade filter capacitors Grounding post Extensive use of ERS Stealth Cloth L-10 power cord Reference Z-Sleeve

Chris Hoff takes power conditioning very seriously. His company, Balanced Power Technologies, located in Defiance, Missouri, specializes in power-conditioning products for audiophiles. Looking through the features list of the BP-10.5 Signature Plus power conditioner ($2999), terms such as Stealth Cloth, Z-Sleeve, and "grain-orientated steel" might sound too sci-fi to be taken seriously. "Snake oil," you might think. But discussions with Hoff are refreshingly free of marketing hyperbole and exaggeration. He describes his approach in a self-assured, no-nonsense way, asserting that these features are what separate his conditioners from the competition. The BP-10.5 Signature Plus represents his latest assault on the electronic nasties that infiltrate audio equipment and rob music of its transparency and flow.

No nonsense, raised to the level of art

One means of approximating an audio component’s "build quality" is by assessing its weight and density. With 75 pounds of nonmagnetic aluminum and passive electronics crammed onto a 13" x 14" footprint, the 10.5 Signature Plus’s build quality is very robust. Add the optional polished-aluminum front plate and the 10.5 begins to resemble Shunyata Research’s attractive Hydra Model-8. The fit’n’finish are excellent, though the 10.5’s chassis has less of the Hydra’s spit-polish appearance.

The 10.5 Signature Plus is a balanced design, which means it conditions incoming electricity with a massive (10 amperes continuous, 20 amperes peak), custom-made toroidal transformer. According to BPT, "The solution is the cancellation of unwanted noise by [Common Mode Rejection], only possible via balanced AC power. A balanced isolation transformer (what’s used inside our conditioners) splits the standard incoming +120V (hot) / +0V (neutral) AC into +60V (hot) / -60V (neutral) components and cancels anything but the pure AC power sinewave when these out-of-phase signals are summed. Your equipment sees a summed 120V source, but the result of CMR is a dramatically lowered noise floor, an improvement in system performance you can see and hear."

Common-mode rejection isn’t new. Companies including ExactPower, Equi-Tech, and Audio Power Industries use the same approach in their products. According to Chris Hoff, BPT is different because every part of the 10.5 has been chosen not only for its name or specification but after exhaustive listening tests. Hoff evaluates each part with his own selections of music. While this may not seem like the most scientific approach, the music does represent a repeatable point of reference.

Five high-quality Hubbell Ground Fault Interrupter (GFI) duplex outlets feed off independent windings of the 10.5 Signature Plus LoNo transformer. According to Hoff, having each GFI run off a separate winding effectively isolates each outlet from the others, which is the equivalent of "install[ing] five dedicated AC circuits for your A/V system." In addition, Faraday shields, copper-foil laminate, ERS Stealth Cloth, and a custom-made Z-Sleeve offer added isolation from magnetic fields as well as EMI/RFI interference into, reportedly, the gigahertz range.

Like its competition, the 10.5 Signature Plus also isolates components from each other; noise from switching power supplies, for instance, should not affect a video display. The heavy-gauge aluminum chassis and solid stainless-steel Iso-Cone feet effectively decouple the chassis from whatever the 10.5 sits on, and hence reduce mechanical noise.

No-nonsense setup

It took five minutes to connect my home-theater system to the BP-10.5 Signature Plus. As per BPT’s instructions, I plugged my Linar Audio Model 10 integrated multichannel amplifier into the outlet closest to the 10.5’s 6’ power cord, while my DVD player, widescreen RPTV, and TiVo had their own duplexes. In the event someone has more than five components, BPT recommends pairing up digital, analog, and video components in each duplex.

At first I wasn’t impressed. The noise floor and overall presentation sounded the same as through the standard wall outlets. Later, I found that I’d accidentally connected my DVD player to the same duplex outlet as the Linar 10. Separating the analog and digital components made a big difference.

Although the BP-10.5 Signature Plus is rated at 10 amps continuous and 20 amps peak, my hefty power amp never had a problem. I also never experienced any tripping of the 10.5’s heavy-duty Carling magnetic circuit breaker. The 10.5 operated reliably, remained cool to the touch, and the music never sounded compressed or starved for power.

A couple of weeks into the review cycle, Chris Hoff sent me an updated version of the L-10 power cord, alleged to improve speed and transparency. I ultimately favored the behavior of the older L-10.

No-nonsense sophistication

I’ve sampled many power conditioners in the last few months. I also own a Shunyata Research Hydra Model-8. Before getting the Hydra, I scoffed at those who swore by the effectiveness of power conditioning. Surge suppression and voltage regulation made sense to me, but "cleaning up power" seemed ridiculous. The Hydra changed my opinion, and now the BP-10.5 Signature Plus has made me a believer in the advantages of balanced power conditioning.

Listening to "Intersection Scene," from John Williams’ excellent score for War of the Worlds [CD, Decca 00456802], revealed another octave of bass response while improving the overall agility and detail across the bass region. This wasn’t the hyped-up, bloated bass that some audio gear produces. It went deeper while revealing tonal detail without exaggerated warmth, and I felt the added weight appeared in the right places. Vocals such as those in Paul Simon’s You’re the One [CD, Warner Bros. 47844-2] were meatier and more pronounced. With my eyes open, it was obvious that Simon was not in the room. When I closed my eyes, the outline of his body was tangible, his voice sweetly ethereal.

Adding the BP-10.5 Signature Plus to my system revealed sparkle and lushness in the high frequencies. Plucked stringed instruments did not sound bright or strident, but naturally rich and chock full of harmonic information. The result was a sound with more dimensionality and sophistication. This quality made Jesse Cooke’s guitar-driven Gravity [Narada 63037] a delectable treat.

The desperate song "Aimee," from the German synth-pop group De/Vision’s 6 Feet Underground [CD, A Different Drum 1214], revealed high frequencies of such texture and harmonic sweetness that the uninitiated may have suspected real instruments in lieu of synthesizers. The BP-10.5 Signature Plus made the heartbreaking chorus and swirling electronic melodies of "Aimee" even more compelling.

Dynamics also improved dramatically. The BP-10.5 Signature Plus’s nonexistent noise floor allowed orchestras to dip, swell, and crash with engaging forcefulness. Leonard Bernstein’s Candide Suite, from Eiji Oue and the Minnesota Orchestra’s Minnesota Orchestra Showcase [CD, Reference RR-907CD], struck a perfect balance between drama and opulence. The soundstage opened up with added depth and atmosphere, filling my room with the sort of "electricity" that makes performances feel alive.

I still remember the moment I first witnessed what the BP-10.5 Signature Plus did for video playback. I was sitting with my son, watching The Incredibles, and noticed how three-dimensional the visuals appeared. I took a moment to dissect what I was seeing as Bob Par/Mr. Incredible and Lucius/Frozone rescued the occupants of a burning building. Inky-rich blacks showcased fiery reds and oranges that seemed to reach beyond the plane of my television screen. I could not believe how dense the colors became. Plugging the television back into the wall revealed a hazier image, with less-pronounced blacks and desaturated colors.

The more I watched, the more I was hooked by what the 10.5 Signature Plus did with images. You’ve heard reviewers wax poetic about how a component drove them to "rediscover" their music collection. Well, the BP-10.5 Signature Plus had me revisiting many DVDs. It did not turn frogs into princes, however, but revealed the flaws of mediocre recordings while being transparent to the virtues of reference recordings. The smeared, overcompressed images of Fever Pitch and Elephant were distracting, as was the anemic sound of Assemblage 23’s Contempt and the Trash Can Sinatras’ Cake.

No-nonsense comparison

I compared several power conditioners with the BP-10.5 Signature Plus. In addition to my resident Hydra Model-8 ($1995), I evaluated ExactPower’s SP15A ($1099) and SP15Ax4 ($1599) balanced power conditioners, as well as Audio Power Industries’ Power Wedge Ultra 115 ($1610).

ExactPower’s SP15A has a single massive 1800W toroidal transformer, the SP15Ax4 four smaller 500W transformers. The SP15Ax4 allegedly isolates noise between components more effectively by using one transformer per duplex outlet, while the single-transformer model trades absolute isolation for higher output capacity per component.

By comparison, the Power Wedge Ultra uses independent, lower-capacity EI transformers on each of its four 120W-rated outlets and one 300W-rated outlet. According to API, EI transformers offer better filtering characteristics due to wider frequency response. The Power Wedge Ultra uses filtering as well as surge protection. The API’s greater flexibility allows users to switch each outlet bank between +/- 60V balanced and 120V polarized mode. Power amplifiers are offered four unbalanced, non-current-limiting isolated filtered outlets

The Hydra Model-8 does not use balanced power, but a special combination of proprietary ferrite material to filter the incoming AC.

Both ExactPower products sounded a bit thin compared to the BP-10.5 Signature Plus. The overall tonality favored a smooth yet cooler, leaner quality. When it came to video, the SP15Ax4’s four individual transformers improved on the SP15A’s single one. Blacks and colors seemed a tad richer and less noisy with the SP15Ax4.

API’s Power Wedge was the closest match to the BP-10.5 Signature Plus. The most apparent changes were with video and digital components -- even my TiVo benefited from balanced power. Output from the disk recorder exhibited cleaner colors and deeper blacks, while the TiVo’s "blocky" compression artifacts were more apparent, but without dancing-mosquito-type noise. My Linar 10 power amp sounded slightly smoother, with less grain. As with the other conditioners, the most obvious changes occurred when I plugged in my DVD player and widescreen television.

Audio was fuller through the BP-10.5 Signature Plus. The Power Wedge Ultra sounded less robust, with a slight decrease in overall tonal color. Video performance was a dead heat. Both products produced cavernous pictures, with brilliant colors and bottomless blacks.

The Hydra Model-8 produced an engaging soundstage. Music flowed from the Hydra with less of the BP-10.5’s texture and tonal color. The BP-10.5 also bettered the Hydra in terms of bass extension and slam. And although the Hydra produced a sharp picture, color saturation and contrast were not as brilliant as with the BP-10.5.

Is it all nonsense?

The BP-10.5 Signature Plus made a huge improvement in my home-theater system. Its ability to filter noise and present music in all its color, texture, and glory at times took my breath away. And what it did for video was absolutely amazing. The rub is that power conditioning does not affect all systems equally. You may also find that your particular system reacts differently to different designs. My advice is to take your time and audition a wide assortment of conditioners while taking advantage of Balanced Power Technologies’ 30-day trial period. If your experience matches mine, you won’t send it back.

Manufacturer contact information:

Balanced Power Technologies
708 Wheatfield Ridge Ct.
Defiance, MO 63341
Phone: (314) 265-1095

E-mail: mailto:contact@b-p-t.com
Website: www.b-p-t.com

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