Mystery Cable Theater

DarqueKnight
DarqueKnight Posts: 6,765
edited October 2007 in 2 Channel Audio
Introduction

During my audio travels I occasionally run across mention of using Home Depot or Lowes 6 gauge power cable for speaker wire. Since this is a slow week, and since I like to make stuff, I decided to drop by Home Depot and pick up a bit of the old Southwire E51585 type THHN 6 AWG single conductor power cable. The wire cost 94 cents per foot, or $3.76 per two conductor cable pair foot. I understand that the wire is a bit cheaper at Lowes and Lowes is actually more convenient to me, but HD has more attractive ladies at the registers. This allows me to practice flirting while shopping for hardware. Now, how good is that? :) I purchased 35 feet of E51585 from which two 8-1/2 foot twisted pair speaker cables were made.

The E51585 cable is a stranded (18 strands if you must know) power cable made of tough pitch coper (TPC). TPC resides at the bottom of the copper wire hierarchy. The copper types differ by the crystal grain structure and impurity content as follows:

PCOCC (Pure Copper by Ohno Continuous Casting)-the annealing and extrusion process for this type of copper results in grain lengths on the order of 350 feet long.

LC-OFC (Linear Crystal Oxygen Free Copper)-reheating (annealing) OFC reduces the number of grain boundaries. The grain lengths are on the order of 6 inches long.

OFC (Oxygen Free Copper)-produced in an oxygen free environment which raises the conductivity up to 2% above that of TPC. The grain lengths are on the order of 1/100th of an inch.

TPC (Tough Pitch Copper) unprocessed copper like the type used in home wiring. TPC contains high oxygen content and many crystal grain boundaries which diminish the detail in complex music signals. The grain lengths are on the order of 1/100th of an inch. This type of copper is generally considered unsuitable for audio cable applications.

E51585 Cable Construction

Red and black rubber boots were slipped on the the ends of the cables to denote positive and negative legs. Two 8-1/2 foot pairs of the cable were securely taped at 6 inches from the end and five twists per foot were made until I reached a point 6 inches from the other end of the cable. My PS Audio Resolution Reference speaker cables came with a set of screw-on banana adapters which just happened to have holes big enough to accomodate 6 gauge wire. Refer to figures 1 and 2.

MysteryCable001640x480.jpg
Figure 1. Home Depot Mystery Cable Prototypes.

MysteryCable002640x480.jpg
Figure 2. Home Depot Mystery Cable Terminations.

As can be expected of wire of this gauge, the conductors are really stiff. However, the twisted pairs had greater flexibility than the individual untwisted conductors and were not difficult to manage.

The Sound

The HD cable was evaluated in my two channel system. The E51585 6 gauge cable has received a favorable recommendation whenever I have seen it mentioned. However, the people doing the recommending never go into detail about their music preferences, associated equipment, and evaluation methodology. Such information for me is readily available from other recent posts, therefore I won't rehash it here.

I will briefly mention my current reference speaker cable, PS Audio Resolution Reference, which has an MSRP of $81.22 per cable pair foot. It is constructed of real, big deal PCOCC copper and currently has over 200 hours of use. The manufacturer's specified break in time is 200 hours.

The HD cable was installed and I was pleasantly surprised. It certainly sounded much better than the Resolution Reference did when it was new. In my review of that cable, I found it to be initially unlistenable.

In going from the broken in, $81.22 per foot Resolution Reference to the brand new, $3.76 per foot Home Depot 6 gauge, this is what I heard:

1. The intruments were in the same lateral positions as with the Resolution Reference, but the depth was gone. Everything was painted two-dimensionally on the speaker plane.

2. There was significantly less bass and high frequency definition. To give you an idea, recordings that were recorded with annoying sibilance sounded smooth and pleasant to listen to. However, recordings with a clear and articulate top end sounded veiled or rolled off. Transient attack of snare drums was slightly blurred and electric and acoustic bass lost a lot of string decay, overtones, and definition.

3. The tactile quality of the bass was gone. I could hear bass, but could no longer feel it. No more bass drum thumping against my chest.

4. Midrange detail was diminished also, but not to the degree of the frequency range extreams. The midrange was actually a bit forward sounding.

5. The HD cable was apparently a bit lower in volume, although it measured the same as the Resolution Reference on the sound level meter.

6. I first installed only one HD cable on the right side and left the Resolution Reference in place on the left. This produced a slight shift in the soundstage to the left. For example, images that were formerly dead center between the SDA 1.2TL's, were shifted over approximately 1 foot to the left. Switching my preamp to mono mode and switching between left and right clearly revealed missing information and diminished overall clarity on the right side.

Conclusion

If I didn't know exactly what I was missing, and had different listening preferences, I could be very pleased with this cable. It is very pleasant sounding. It reminds me of some tube gear that I have heard, and I do not mean that derisively. Someone wanting to tame a system that tends toward brightness or who prefers a forward midrange might like this cable a lot. As of this writing, I only have three hours on the HD cables. I'll listen to them a few more days and report back on any sonic changes that occur.

Even if it turns out that this cable magically transforms over the next few days and I grow to like the sound of it cable more than my current reference (:eek:), I would have some serious concerns about long term performance degradation as the cable ages and oxidizes over time. The base metal and insulating jacket are not specified for audio applications.

To Be Continued
Proud and loyal citizen of the Digital Domain and Solid State Country!
Post edited by DarqueKnight on

Comments

  • DarqueKnight
    DarqueKnight Posts: 6,765
    edited October 2007
    After 30 hours of play time at average sound levels of 85 to 92 dB, the high frequency detail improved a bit. The soundstaging is still two dimensional and flat as a pancake. The pancake is beginning to annoy me now. In all the good "reviews" and comments I have read about this cable, no one has ever mentioned it's imaging and soundstaging characteristics.

    According to the wonderful people at audioasylum.com and other online forums, this cable is supposed to break in sometime between 25 to 75 hours. I'll never reach the 75 hour mark because my PS Audio cables are going back in today.:)
    Proud and loyal citizen of the Digital Domain and Solid State Country!
  • Polk65
    Polk65 Posts: 1,405
    edited October 2007
    DK looking for the girl from Ipanema at HD... who would have thunk? It'll be interesting to hear if these blossom.
  • PolkThug
    PolkThug Posts: 7,532
    edited October 2007
    6awg seems massive for speaker wire. What gauge is the PS Audio wire?
  • DarqueKnight
    DarqueKnight Posts: 6,765
    edited October 2007
    The PS Audio Resolution Reference is 11 gauge.
    Proud and loyal citizen of the Digital Domain and Solid State Country!
  • PolkThug
    PolkThug Posts: 7,532
    edited October 2007
    The PS Audio Resolution Reference is 11 gauge.

    Makes sense, the diminished higher frequencies that you observed correspond to the increased capacitance of 6awg wire.