September 2011

GutWire Uno-S & Eon-Z Interconnects Plus SP-11.1 & SP-CE Power Cable
Good cables don't come cheap yet expensive cables may fail to convince.
Review By Phil Gold

  An unusual assignment – would I like to pull all the cables out of my system and replace them with the latest offerings from Toronto-based GutWire? I'll try anything in the name of science, so I quickly agreed. GutWire have been in business of making cables since 1999, adding power conditioners and other accessories along the way. They sell across North America (62 retailers in the United States alone), Brazil, Mexico, the UK and Asia. They follow a clear design philosophy, based on empirical results. They use cold-welding (crimping) for all terminations, high purity oxygen-free copper in unique wire-weave patterns, and sophisticated shielding to reject Radio Frequency Interference (RFI) and Electromagnetic Interference (EMI). They will have nothing to do with capacitors, coils or resistors as some high end manufacturers have done. Their cables are all handmade and individually tested in their own workshop following which they recommend an extensive burn in period of 100 hours for best performance.

Over the course of several months GutWire made up a set of cables to match my requirements:

1 pair of Uno-S Interconnects 1M XLR    - $3045 a pair

1 pair of Uno-S Interconnects 2M RCA   - $3582 a pair

1 pair of Eon-Z Interconnects 1M XLR    - $2055 a pair

1 pair of Eon-Z Interconnects 2M RCA   - $2261 a pair

2 SP-11.1 6' power cable                      - $4409 per cord

1 SP-CE 6' power cable (Crystal Edition)  - $1979 per cord

1 SP-6.1 6' power cable                          - $1705 per cord

Six Bar AC line conditioner                      - $2729

Sadly the development of the new Vision speaker cable ($8999 for a single wire pair of 8' length) was not complete in time for this review, so it will have to wait for another occasion. This was my first in-house experience of GutWire cables apart from an excellent red power cable I tried many moons ago. The package of cables they brought over includes their very latest designs.

The Uno-S is their top of the line interconnect, with the Eon-Z one level down from that. The 6 Bar AC Line Conditioner, which weighs a ton, is a beautifully finished unit with the power input on one side, six outlets on top and the name GutWire shot right through a thick extrusion to the base. It fits between the 4 Bar and the MaxCon Extreme. The SP-11.1 sits one notch down from the top in their list of power cables, the SP-CE two notches further down and SP-6.1 just below that, with SP-3.1, SP-5.1, SP-8.1 and SP-18.1 rounding out the range, and that's before we take into account 5 other models shown on the web site. That's a grand total of 12 power cables – GutWire takes power cables seriously!

The Uno-S interconnects and all the power cables provided have separate sheathing for positive, negative and ground, increasing the bulk but allowing flexibility. The other cables have single sheathing and are also quite flexible. The mesh covers are loose, and the connectors are not the usual run of the mill kind. The XLR connectors are extremely high end Xhadow Precision devices, whose barrel is lathed from pure aluminum rod-stock. The angled bananas are euro-spec WBT 0645 devices, ready for bi-wiring, and with thumbwheel adjustment of the expanding inner spike.

The SP-6.1 Power cable sports a yellow clad Marinco 8215T Hospital Grade AC connector and a 15amp Wattgate IEC connector, sheathed again in yellow, while the cable itself has three back mesh covered twisted cords with Mylar metallic braid shielding and both air and Teflon insulation. Conductors are solid-core high purity oxygen-free copper. The SP-CE cord has a white/silver finish and white sheathing around the plugs, with an upgraded Wattgate 330i Audio Grade AC connector. Both cables have a diameter of just under 1".The upscale SP-11.1 is thicker at 1.25" and rather less flexible, has a black mesh cover and a grey cover over each plug. It is terminated with a Wattgate Audio Grade 350i IEC connector.

The interconnects were a pleasure to use, but I did have some difficulty with the power cables, especially the thicker SP-11.1. While they bend reasonably well, they are resistant to twisting. So if the pins do not line up optimally with the connectors on the back of your components you could be in for a fight, especially if space is tight. You need a depth of at least 12" behind your components with the SP-11.1, compared to 8" for a Dynamic Design Spirit-C or 6" for the Nordost Valhalla. I had to relocate the GutWire line conditioner from a position on the top of my purpose built cabinet to the floor in front of the cabinet. The Valhallas are not the supplest cables either, but they are much easier to accommodate. So my word of caution here is to try them out at home before committing.

You install cables once, but you listen all the time, so how do they perform in everyday use? I set up a very transparent system to test out these cables. The Digital source and preamp both hail from EMM Labs, the XDS1 and Pre2 respectively, while the power amp is the 300wpc Bryston 4BSSTฒ. I used a variety of speakers: the Wilson Benesch Act1, Totem Element Metal and YG Carmel. I also tried a vinyl source - the Linn Sondek LP12, Ittok, Clearaudio Virtuoso Wood and AVID Pulsus. Since the Vision speaker cables were not available I used my reference Nordost Valhalla bi-wires in their place.

I was delighted by the performance of the two SP11.1 Power Cables on my amp and preamp while the SP-CE did equally well with the CD player. My previous tests of power cords have shown them to play a vital role in a system of this caliber, and these cables are the first I've had in house to fully measure up to the Valhalla power cords. $4409 will buy you a 2M length of SP-11.1 and the Valhalla equivalent runs $3900. In fact the SP-11.1 has all the reflexes and silent background of the Valhallas with the bonus of a little extra solidity. The SP-CE falls behind in low frequency definition and attack when asked to power a hungry beast like the Bryston but seems very well attuned to the lower current demands of the two EMM Labs components.

The system proved equally happy in Bach and Miles Davis, Joan Baez and Shostakovich. There's an excellent jump quality to the sound with no compression or blurring on sudden transients like you'll find in the first movement of Shchedrin's Second Piano Concerto with Marc-Andr้ Hamelin and the BBC Scottish orchestra under Andrew Litton [Hyperion SACDA6742], which can really reveal dynamic weaknesses. The cables preserve spatial information very well, giving a full orchestra a solid 3 dimensional feel, performing the same service with small jazz combos like the Holly Cole Trio [Blue Note CDP 7 81198 2]. In this regard, they are the equal of the reference Valhallas. There is certainly a touch more warmth, but also slightly less low level detail and blackness between the notes, although it takes very careful listening to sort out these differences. The stellar piano sound on Robert Silverman's Mozart Sonata box [Isomike 5602] gives the system a good workout, and the result is a remarkably piano sound, deep, harmonious and spacious. In terms of color they are very revealing of the differences between voices within small groups or the instruments of the orchestra, and they made all the detail of Joan Baez's "Diamonds and Rust" crystal clear [Vanguard VCD 125/7] and firmly located.

If you are looking for cables to warm up the sound of an otherwise sterile system, I could give you some names, but GutWire would not be on the list. They are shockingly and brutally honest, quick to reveal faults elsewhere in the chain, and should therefore only be used if you are already happy with your electronic components and speakers, and just want to hear them to their best advantage. If on the other hand your system is already warm then the GutWires may be just the ticket to keep a good balance.

A high quality power distribution box is an important consideration in a high-end system and the 6 Bar Power Conditioner provided a solid partner in this system, although time did not permit A/B comparison against the reference Thor unit. You should note that the 6 Bar does not offer any protection against lightning. GutWire believe such protection comes at the cost of sonic purity, and recommend instead buying an AC receptacle from Hubbell with surge protection built in if you want to go that route.

In this review I did not compare the GutWire Cables to significantly less expensive alternatives, so you may want to take a look at some of my earlier reviews of power cables and interconnects, none of which could hold a candle to the reference Valhallas. See my other two cable review shootouts at this link and this link.

Good cables don't come cheap in my experience, but it is equally true that many expensive cables fail to convince. Although the Vision speaker cable review will have to wait, GutWire's power cables, interconnects and power conditioner combined to allow all the components at my disposal to work their magic, and they should certainly be on your short list for audition.

Specifications
Eon-Z Interconnect
• Conductor: 20 AWG Solid Copper with Teflon Insulation. 
• Conductors: High Purity Oxygen-Free Copper (HPOFC). Low loss dielectric. 
• Insulation: PVC Tube Air Insulation 
• Shielding: 100% Mylar Metallic shielding 
• Terminations: Cold Soldering 
• Option: Xhadow XLR

Uno-S Interconnect
• Conductor: 16 AWG Solid Copper with Teflon Insulation. 
• Conductors: High Purity Oxygen-Free Copper (HPOFC). Low loss dielectric. 
• Insulation: Dupont TEFLON PFA tube. 
• Shielding: 100% Mylar Metallic shielding 
• Terminations: Cold Soldering 
• Option: Xhadow XLR

SP-6.1 Power Cable
• Cable Diameter:0.975" 
• Conductors: Solid Core High Purity Oxygen Free Copper 
• Shield Coverage: 100% Mylar Metallic braid shielding 
• Shielding Type: Air Insulation with individual shielding 
• Insulation: Dupont TEFLON 
• Extensive use of natural minerals: Binchō-tan 
• Electron Rectification Processing (ERP): Level 1 
• Conductor Current Carrying Capacity: 78 
• IEC Connector: Wattgate 320i 15A or Hubbell 20A 
• AC Connector: Marinco 8215T Hospital Grade or Wattgate 350i HC 20A 

SP-Crystal Edition Power Cable
• Cable Diameter: 0.988" 
• Conductors: Solid Core High Purity Oxygen Free Copper 
• Shield Coverage: 100% Mylar Metallic braid shielding 
• Shielding Type: Air Insulation with overall shielding 
• Insulation: Dupont TEFLON 
• Electron Rectification Processing (ERP): Level 1 
• Extensive use of natural minerals: Binchō-tan and Amethyst 
• Conductor Current Carrying Capacity: 80 
• IEC Connector: Wattgate 320i 15A or Hubbell 20A 
• AC Connector: Wattgate 330i Audio Grade or Wattgate 350i HC 20A

SP-11.1 Power Cable
• Cable Diameter:1.25" 
• Conductor Diameter:.25" 
• Conductors: Solid Core High Purity Oxygen Free Copper 
• Shield Coverage: 100% Mylar Metallic shielding 
• Shielding Type: Air Insulation with individual shielding 
• Insulation: Dupont TEFLON 
• Electron Rectification Processing (ERP): Level 2 
• Extensive use of natural minerals: Binchō-tan 
• Conductor Current Carrying Capacity: 112 
• IEC Connector: Wattgate 350i 15A 
• AC Connector: Marinco 8215T Hospital Grade or Wattgate 350i HC 20A

6-Bar Power Conditioner
• The top chassis is milled from solid block of aircraft-grade aluminum and the bottom plate is 1/2" thick for extremely low resonance. 
• Equipped with two Hubbell HBL8300R 20A hospital-grade receptacles and one Hubbell IG8300R 20A hospital-grade isolated-ground receptacle. 
• Equipped with Furutech FI-10 high performance IEC. 
• All the internal wires are GutWire 16AWG solid core high purity oxygen-free copper cables with Teflon insulation. 
• Point to point wiring. The cable path is connecting between the IEC inlet and receptacles directly. Our filter is running parallel to the AC line. All the termination is done without soldering. 
• ERPi (Improved Electron Rectification Processing): Level 3. 
• Extensive use of natural minerals like Binchō-tan and Microcrystalline Quartz. Both minerals can release negative ions and far infrared (FIR) which helps to improve the flow and "cleanness" of the AC current. Binchō-tan is connected directly to the ground for better absorption of noise.

Price
Uno-S Interconnects 1M XLR    - $3045 a pair
Uno-S Interconnects 2M RCA   - $3582 a pair
Eon-Z Interconnects 1M XLR    - $2055 a pair
Eon-Z Interconnects 2M RCA   - $2261 a pair
SP-11.1 6' power cable           - $4409 per cord
SP-CE 6' power cable (Crystal Edition)  - $1979 per cord
SP-6.1 6' power cable   - $1705 per cord
Six Bar AC line conditioner - $2729

Company Information
GutWire Audio Cables
9251 Yonge Street
Suite 8267
Richmond Hill, ON
Canada L4C 9T3

Voice: (905) 370-1139 
Fax: (905) 370-1140 
E-mail: gutwire@gutwire.com
Website: www.gutwire.com