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Reviewer: Paul Candy
Source: Eastern Electric Minimax CD player, Audio Zone DAC-1 [in for review], Pro-Ject RPM 5 turntable w/Ortofon Rondo Blue cartridge
Preamp/Integrated: Manley Labs Shrimp, Audio Zone AMP-1, Pro-Ject Tube Box phono stage, Audio Zone PRE-T1 [in for review]
Amp: Manley Labs Mahi monoblocks, Audio Zone AMP-2 monoblocks [in for review]
Speakers: Green Mountain Audio Callisto (on sand filled Skylan stands), Gemme Audio Concert 108i [in for review], JM Reynaud Twin Signature [in for review], REL Q108 Mk II subwoofer
Cables: DH Labs Revelation, Air Matrix, Acoustic Zen Silver Reference interconnects, Auditorium 23 speaker cables, DH Labs D-75 digital cable, Audience Maestro interconnects and speaker cables
Power Cables: GutWire Power Clef², C Clef, Audience Powerchord
Stands: Premier three-tier, filled with sand
Powerline conditioning: BPT Pure Power Center w/Wattgate 381 outlets w/ Bybee Quantum Purifiers and ERS cloth
Sundry accessories: Grado SR-60 headphones, Pro-Ject Speed Box, Gingko Audio Cloud 11 platform, Skylan damping boards [in for review], Grand Prix Audio APEX footers, Isoclean fuses, Walker Audio SST contact enhancer, Walker Audio Ultra Vivid, Audio Magic/Quantum Physics Noise Disruptors, GutWire SoundPads, Herbie's Way Excellent Turntable Mat, dedicated AC line with Wattgate 381 outlet, Echo Busters acoustic room treatments
Room size: 11' x 18' x 8', short wall setup, hardwood floors with large area rug
Review Component Retail: X Clef² $2,999; B-12 $30 per foot; Lock $799
While cruising the halls of the Montreal show this past winter, I ran into GutWire's Herbert Wong and Alex Yeung - two exceedingly pleasant fellas. Since I'm a big fan of their power cables as well as their SoundPad and NotePad resonance control pillows, I was curious to see what they had been up to lately. Herbert showed me a trio of new DIY-based cables including the B-12 power cable covered here, as well as a neat spring-loaded outlet plate called the Lock, which firmly grasps big heavy power cables with an iron fist. Needless to say, I was interested in reviewing both. Then Herbert -- with a wry smile knowing my budgetary leanings -- asked if I wanted to "try something crazy" and showed me the X Clef² power cable. Since "crazy" is my middle name, I replied in the affirmative before asking what he had in mind, exactly. But I agreed to drop by GutWire's Richmond Hill, Ontario office in a couple of weeks to collect my booty. After pick-up, I connected the X Clef² to my Wattgate wall outlet and BPT Pure Power Center which supplies juice to my entire system. I promptly forgot about it for the next few weeks as it burned in. In the meantime, I assembled the B-12.


The inch-and-half thick X Clef² is GutWire's top-of-the-line power cable. It consists of Teflon-insulated high-purity oxygen-free copper surrounded by several layers of shielding, a GutWire hallmark. IEC and AC connectors are Wattgate 350i and Wattgate 330i respectively. The X Clef² also features GutWire's GERP or GutWire Electron Rectification Processing. Herbert is tight-lipped about what GERP is. My guess is some sort of ferrous material. As in all of GutWire's cable products, the X Clef² features crimped terminations. During extensive listening sessions, GutWire discovered that crimped connections outperformed soldered ones. The X Clef² also sports a proprietary damping material at the rear of the IEC connector to reduce resonance. While thick as a python and about as heavy (don't ask how I know), the cable was relatively flexible and even attractive in its dark grey mesh sleeving. As with all of GutWire's power cables, the X Clef² sports a short flying lead connected to the outermost shield and an alligator clip on the free end. This offers the option to float or ground the outermost shield to the chassis of connected equipment. GutWire believes this can affect sound quality. I've tried floating and connecting the leads on GutWire's cables several times over the past couple of years and I can't say I have ever noticed much of a difference if any. Having said that, I certainly appreciate having a choice.
The B-12 is GutWire's DIY power cable available right off the roll at $30/ft. The B-12 is UL and CSA approved and features polyethylene-insulated HP-OFC conductors surrounded by a tinned copper-braided shield and Mylar wrap. There are four polyethylene spacers for minimizing crosstalk between the various conductors. The outer covering is bright blue PVC.


Assembling the B-12 was a relatively painless affair. I had a $7.50 Marinco 5266 AC plug and $20 Wattgate 320 IEC connector on hand. First, I decided whether or not to float the shield at both ends or just at one end. There are no fast and hard rules. I've seen all sorts of shielding arrangements with various power cables. However, the general consensus is the shield should be grounded at the plug end to supposedly drain any picked-up noise away from the attached component. That was how I configured the B-12. For the IEC end, I removed approximately 1" of the outer insulation and snipped away the redundant poly spacers and braided shield. I then stripped off the appropriate amount of insulation from the conductors, twisted the bare copper strands together, applied a dab of Walker SST, inserted the conductors into the labeled channels of the IEC connector and tightened the screws down hard. I then slid the outer shell over the cable, connected it to the wired portion of the IEC and then tightened the screws on the strain relief for a good solid fit. You don't want to strip off more than an inch of the outer insulation as the strain relief will contact the conductors directly instead of the outer PVC. The same applies for the AC plug end, except I stripped off 1 ¼" of insulation. Instead of removing the braided shield, I unraveled it and twisted it together with the ground wire. I also trimmed off some of the excess braid. I applied some SST to the bare copper strands and to the male blades of the AC plug once I completed assembly.


Rolling your own power cables makes a lot of sense. Since a good portion of the cost of a preassembled cable is labor, one can save a considerable amount. A 6" length of B-12 will run you $180 plus whatever you choose for connectors. So for a little over $200, you can construct a cable that might normally retail for two or three times that. Mind you, there are other considerably less expensive bulk cables you could buy and save even more on. How they would compare to the B-12 I cannot say of course.

After a few weeks' burn in, I swapped out the X Clef² for my current reference, the Power Clef². There was quite a difference between the two cables. Switching back again from the Power Clef feeding my entire system via BPT's PPC to the X Clef² frankly surprised me. While I expected to hear some improvement, I didn't expect this much. Simply put, it was akin to blowing up a dam. Music just burst forth with far greater impact. Oddly, the volume seemed louder as well. Image density is something else I noted. Instruments and voices exhibited greater presence. Dynamics improved. The shift from soft to loud was both more sudden and with greater delineation. The mids and highs were clearer, with even less noise, edge or hash. Music playback essentially became more believable, more real. I can't say that the step up from GutWire's $999 Power Clef² to the X Clef²'s $2,999 price is worth paying three times the price for. At what point the law of diminishing returns kicks in for you will depend on your system, your listening bias and your relationship with your bank manager and/or significant other. But brother, this power cable did deliver the sonic goods in a big way in my system.


Compared to other power cables I've tried -- including models by Wireworld, Harmonic Technology, BPT, Audience -- the X Clef² beat all contenders in noise reduction, bass weight, image density and tonal richness. Furthermore, there was a beguiling smoothness and relaxed ease that reminded me of what decent tube amps can offer. I'm at a loss to explain why a mere 5.5' long power cable can have such an impact on a system's performance but that's what I heard.


Some power cables such as the Audience powerChord and BPT's unshielded L-10 major on speed, dynamics and openness whereas the X Clef² leaned towards the warmth and enhanced body end of the spectrum - but minus the bloat and sluggishness which I noticed a little of in GutWire's previous generation of power cables. A year ago when I reviewed the Power Clef², I recall Herbert explaining that one of the primary areas addressed in the updated lineup was in the conductor insulation. Lossy dielectrics can exhibit a blurring effect on a cable's performance, be it interconnect, speaker cable or AC cord; hence the shift to Teflon in some of GutWire's cables. Teflon has less dielectric involvement than PVC or polyethylene.

I also tried the X Clef² in a stripped-down system featuring my AMP-1, Minimax CDP and JM Reynaud Twin Signatures. I connected my components directly to my Wattgate wall outlet. In my experience, the effects (good or bad) of power cables have with few exceptions been far more noticeable with amplifiers than with any other component. The same was true here with the cable connected to my AMP-1. There was that dam-busting effect again. It's as if the power rating on my wee chip amp was doubled if not tripled. As in my main system, I also noted enhanced noise reduction, greater harmonic complexity and relaxed ease. Attached to my CD player, I noted less in the area of enhanced power and dynamics but more in terms of noise reduction, smoothness and a wider, deeper soundstage with greater ambient info retrieval.


The B-12 was not quite in the same league as the X Clef² but it was miles beyond any stock cord. Like all of GutWire's AC cables I have sampled, the B-12 exhibited the same signature effects I noted above, just to a considerably lesser degree than the X Clef². The B-12 receives a thumbs up and is worthy of consideration for DIY cable projects.

When Herbert emailed me the retail price of the Lock, I honestly thought the $799 was a typo. When I discovered that figure was indeed correct I asked Herbert to explain why the Lock was so expensive. "The main reason for the lock to be that price is that it requires many machine hours to make. If you look at the construction of the box, you can see the "lid" and the "box". The "box" itself is milled from a solid block of aluminum which means there is more than 90% of waste to mill out the box. The 2 clamps inside are the same. They are milled from one block of aluminum and most of the material is bored out to form that shape. We are talking about a lot of waste and
machine time here. All of these factors contribute to the cost of the lock."


The Lock is a handy device and indeed works as advertised. Due to the weight of the X Clef², it hung at an uncomfortable angle from my wall outlet without Lock support. With the Lock installed, its spring-loaded clamps kept a tight hold on the X Clef² and prevented sag by 100%. While certainly effective, I cannot recommend it given its astronomical retail price. At $79 or even $100, I'd be singing a different tune. Even with Herbert's explanation, I fail to understand why this handy accessory costs so much. There must be another way to accomplish the same task at a lower cost.

The X Clef² is easily the best power cable I have tried but it is also the most expensive. The $2,999 asking price might seem obscene to some. However, GutWire has far less expensive cables in its lineup to suit any budget. If it helps, think of the X Clef² as a power conditioner built into a cable. Put in that context, it doesn't seem too mad perhaps. Furthermore, just one X Clef² feeding my entire system performed better than many stand-alone power conditioners I have tried. While I doubt I could ever justify spending $3000 on a power cable, I will certainly miss the X Clef². I can only imagine what results I would reap with all my components wired up in such royal fashion.


If you are considering testing the power cable waters with a limited budget, my advice is roll your own or buy the one best you can afford and either run it to your amp or better yet, connect it between your wall outlet and either PLC or a high- quality power bar such as offered by BPT, PS Audio or Wireworld. That way you can share the luv with your entire system without beating your wallet into the dirt. Then perhaps three grand for a killer power cable doesn't sound too crazy after all.
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