Positive Feedback ISSUE 71
hb cable design
PowerSlave Acrylic Distributor
as reviewed by Marshall Nack
"What's this?" I expected a power distributor, but this shipping box is large and heavy enough to mandate a luggage cart for haulage. Then I recalled Brian Ackerman, the importer of HB PowerSlave products, telling me that first look would be a shocker.
The HB PowerSlave Acrylic is one of those massively over-built products that defies reasonableness and makes you wonder—why? I'm telling you this to prepare you, in the event you order one of these. Photos do not do it justice. It dwarfs the other power products I have and its build quality leaves them all in the dust as well—it's out of this world. Some products instill pride of ownership—this is definitely a power distributor for the luxury class.
Design and Construction
As we continue, please keep in mind that the object under observation, the HB Acrylic model, is a true passive device. Some passive power devices have electrical components inside, such as capacitors and resistors. Others contain material purported to possess noise filtration or vibration absorption properties. I think these are more accurately described as passive conditioners.
The power distributor's housing is Polycarbonate "Makrolon" acrylic glass, a transparent material known for its non-resonant or dampening qualities. It is similar to the acrylic used for many turntable platters.
As you can see, there are no capacitors/resistors/magic dust inside the HB. What lurks within is proprietary conductor wire constructed from a hybrid of silver and copper. (The company has a highly regarded line of signal wires and power cords.)
The conductors are ensconced in multiple layers of dielectrics, which perform either dampening or shielding functions. The dielectrics are chosen depending on their usage; that is, where a particular wire will be deployed.
The eight AC outlets did not look familiar; they are custom made in Germany. The IEC plug is also of custom German manufacture. All of the contacts are solid copper alloy with two-layer gold plating.
The Benefits of a Passive Device
I think it's reasonable to assume a passive distributor will share characteristics with other passive devices, such as preamps. The benefits of these are well known. Number one is sky-high purity quotient. Passives, by definition, don't subtract info and they're not supposed to add artifacts. They don't muck around with timbre and they usually enhance body. They are prized for sounding less mechanical, more acoustic.
The Drawbacks of a Passive Device
The drawbacks of passives are also well known. Typically, dynamics take a hit, transients acquire a rounded edge, and treble is softened. All of these, in turn, negatively impact speed.
Often the soundstage becomes recessive. Finally, passives do not clean up power line grunge. That is left to the conditioning built into your components. Hopefully, they're up to the task.
But How Does it Sound?
OK. The looks of the Acrylic are incredible—what about the sound? The HB confounds nearly everything I just wrote about passive devices.
After adequate burn-in, I plugged my front-end into the HB, now consisting of either the Veloce LS-1 or Trinity preamp, and the Metronome D6 DAC and Calypso transport or Accuphase DP-600 SACD Player. I experimented a bit to get a feel for what the HB was doing and, after optimization, it wasn't long before listeners began commenting, "Man, this is another sonically stunning CD." Disc after disc.
I must say, the HB mated splendidly with the Metronome digital. The months spent with the Metronome plugged into the HB were of such rare and exalted caliber, it took your breath away. The already fabulous Metronome attained higher stratospheric orbit. Nearly every CD elicited that same comment.
I would occasionally take a step back and ask, "OK. What's it not doing? What's not happening?" Silence would then prevail in the listening room. Everything about the presentation was as it should be.
I put on the Michael Tilson Thomas, San Francisco Symphony SACD of Mahler Symphony No. 2, (SFS 821936-0006-2). I have never understood why respected critics held these MTT recordings in such high esteem. I always found them sub-par, both for sonics and performance. "What's the big deal?" was my take. Now, however, it held us spellbound and we stayed put through the entire performance. I noted, but was not overly bothered by, MTT's liberties in interpreting the score.
The HB has the biggest impact on frequency linearity. Without the HB, frequency response was lumpy, with some bands bulging, others too scant and a lot of blending. The sound was both non-linear and flabby. As far as staging, one instrument overlapped or bled into the next, just as midrange spread into bass.
The HB acted like a girdle or corset. It sucked in the fatty areas—anything loose got pulled in and made firm—and frequency response became linear. The only exception was a slight bump in the bass region that was really marginal. (I'm not complaining—most systems can benefit from a firm boost down there.) Think of the HB like Spanx for your systems frequency response.
Some Things I Don't Understand
Some things I don't understand, like how the HB empowered dynamics: Dynamic range exploded; potency was injected into the bass region. My panel-mate Sheldon came up with a good analogy. It's like going from a full-range speaker with a single 8" woofer, to one with the same response but multiple 8" drivers. The latter is always more convincing (and enjoyable) because it is able to get more air in motion.
The signal purity quotient is extremely high and, somehow, the transient edge sharpened up. Speed is amazing. Folks, this passive is as good as—nay, even better than—any active device I've come across.
A word of caution. Not every component needs a girdle. The Vitus SP-102 Phono Stage I'm using at the moment doles out weight and body in exactly the amount required as appropriate to the source. There is no excess fat. Putting a girdle on the Vitus started to encroach on lean and analytic.
The HB Cable Design PowerSlave Acrylic Distributor does some wonderful things for your power line. When I consider that the object under observation is a passive device, I'm dumbfounded. It sure ain't conforming to expectations about that kind of device. I'm simply at a loss to explain what I'm hearing.
When I added the HB Acrylic to my system (there are three models; the Acrylic is in the middle), it achieved the tipping point that catapulted the Metronome digital front-end into an elevated, stratospheric orbit.
Bottom line: If I had an unlimited budget, I'd sooner purchase the HB Acrylic than any power distributor or conditioner on the market. Marshall Nack