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In Reply to: RE: DC Cable Comparisons posted by Jon L on October 10, 2020 at 19:53:54
after building many prototypes, for some time i believed the VH Audio unicrystal OCC solid copper in Airlok to be the best for this application, but then i discovered something WAY better: Duelund AWG 20 CC08, solid copper wire, in cotton & oil insulated
two runs twisted makes a probably unbeatable DC cable; not easy to solder though, but once done it's really great; i believe this is due to the fact that no plastic is involved at all; as usual, this is to my ears, in my system, for my music and taste
i'm using one just now... :)
Follow Ups:
I've used both Western Electric and Duelund tin-plated copper wire for signal applications, and at this point, I'm not sure I like this "tone wire" sound.
Then again, DC is a different animal, and the stuff is inexpensive enough to experiment. I just don't want to lose significant amount of transparency and top-end extension.
Shielding your DC cable with an external braided shield (and a drain wire attached to the end points of the shield) made a great improvement in my setup.
It is called JSSG 360, and there is a lot of info about this subject on the computer audiophile website. It creates a faraday cage around your cable and blocks leakage current from stray voltages generated inside your cable or from induction of external sources.
I have it applied on DC, USB, Ethernet and have gained massive noise reduction (blacker background) in my setup. Some people doubt the shielding effectiveness (compared to unshielded, floating shield, one end connected shield etc...), but my ears tell me something else.
My current DC cable is a mundorf silver gold in starquad with JSSG 360 shield. I haven't tested duelund yet.
Have you tried A-B listening comparisons with the external wire on vs off the shield?
BTW, how did you get the Mundorf wire into star quad geometry, hand twist?
Good point, TanteJuut. Experiments with braided copper shielded twisted pair DC umbilical builds provide notable benefit.
The self-shielding geometry of a cross-connected star quad VH Audio V-Quad DC umbilical is very beneficial in this regard.
nope, this is no tinned, just solid copper, being the dielectric the important element: cotton in oil
nt
Dear Jon.
I have made the starquad myself. The measurements on the JSSG 360 tweak shows no improvement. I have read also a paper on ASR about this subject (and the explanation of John Swenson himself). The ASR folks could not find a plausible explanation or effect of the self shielding. But, maybe they are measuring the wrong parameter. My hypothesis is that residual AC on the DC line (through parasitic capacitance, inducing a voltage and causing leakage current) is being shunted by the self shielding braid, and that picked up/sent out RFI is shunted also (reduced antenna effect). Maybe the tweak is beneficial for other cables/the cable salad behind my rack (less noise pick up) and is the performance gain more indirect.
I have investigated this tweak with multiple cables (DC, USB, interconnects, ethernet) and there is always a reduced noise floor in my system (bigger & tighter bass, blacker background, more air/halo's around individual elements in the mix) when I applied this tweak. I am not an advocate of shielding everything because it can choke the sound. I just experiment back and forth until I am happy.
With kind regards, Judith
Hi TanteJuut,
A typical unshielded zip cord or twisted pair DC umbilical can attract RFI and is vulnerable to EMI due to the inductance of the conductors. The self-shielding aspect of the cross-connected star quad geometry helps to control the magnetic fields and lowers inductance considerably, as well as providing substantially better noise cancellation of RFI that rides on the DC umbilical. A DC umbilical with a braided shield can also be beneficial, with the most critical DC umbilical of all in my collection being a shielded design. The additional capacitance might even be of some benefit in terms of noise reduction.
Unless I'm completely unaware of the difference between a DC umbilical and internal DC wiring, AC is not an issue to consider any more than AC is something to be concerned about in terms of the internal wiring of a power supply section of an audio component without an external power supply. There is no metal enclosure to shield an external DC umbilical vs. internal DC wiring, and any internal wiring is in fact more prone to AC noise than a DC umbilical, as internal signal wiring often needs to be shielded with a braided shield unless a listener enjoys the sound of horrific hum produced by the adjacent power supply section located within the enclosure.
If any articles or reports are found that support the notion of AC otherwise affecting a DC umbilical, I'd be pleased to know any links to them.
Cheers, Duster
Hello Duster,
I will post them ASAP. It is a personal hypothesis. I am investigating the effect of AC/DC leakage currents, parasitic capacitance and stray voltages on audio equipment. I think the JSSG 360 Loop breaks unwanted low level current flow between components.
At the end, my ears tell me that it works. I am also eager to find a good explanation why this kind of shielding works.
Cheers Juut
I found some information about the tweak and don't agree with the premise. I discontinued reading when the single grounding point of a Faraday cage seemed to be a disagreeable thing. The image shown above is involved with a metal outdoor shed that acts as a Faraday cage. It's a single ground wire with a strap to be attached to a metal pipe or rod as an earth ground. Affixing yet another wire to the braided shield of a cable and attaching it someplace where it does not belong might be a measurable thing, but it's not a Faraday cage which has been successfully implemented by just about any field of interest for the purpose. If the fellow wants to fiddle with such a thing, there should be no unreasonable claim of superiority vs. a classic Faraday cage, IMO.
The closed loop of the shield wire is responsible for the noise reduction effect and creating an effective faraday cage. A lot of folks on the computer audiophile website reported the same effect in their systems. If you want an explanation from me or you just want to say that you are not (scientifically) convinced, then I am fine with that. That happens always with audiophiles. I shared my experience & I am happy with the results. Enjoy your sunday.
Juut.
Audiophiles are a curious bunchThey 'believe' better sound is achievable, as evidenced by their constant buying [upgrading, tweaking etc]....but are never convinced when someone claims to have achieved better sound.
In essence they believe something to be true, but deny anyone who claims to have actually made it happen.
Then there are those who can imagine better sound just by reading numbers. I even read a post where someone could actually here jitter in the Pico-seconds....ie That is one trillionth, or one millionth of one millionth of a second, or 0.000 000 000 001 seconds.
Amazing!!!For example, these days your Dac is crap if it doesn't have a "Femto-second" clock. DACs with clocks with only accuracy in the Pico-seconds just don't sound as good due to all that nasty jitter. People will swear they can easily hear a Femtosecond clock vs a Picosecond clock. Femtosecond - A femtosecond is equal to 1000 attoseconds, or 1/1000 picosecond...wow! Imagine that!!! 50+ year old ears that can hear that well, when hearing only gets worse with age. I'd imagine they could hear so well at 20yr old that they could hear what people were thinking.
And wire is another story....6N silver all over the place....which is actually purer than anyone can achieve. But hey, an Audiophile can easily hear the difference between 4N [probably the most expensive and purest] vs the magical 6N.
Dynobots Audio - Music is the Bridge Between Heaven and Earth
Edits: 10/18/20 10/18/20
I am not making a claim. I have said already that I have personal hypothesis about this subject. And that is currently the right position for my point of view. Calling it fiddling is belittling. Swenson and the folks on ASR and Computer Audiophile are also thumbling around this subject and there are some great engineers that can not explain nor measure the effect either. I know that Phasure USB is going over the top with multiple interconnected shields (and getting good reviews)
By connecting a thin wire between the end points of the braid you form a closed circuit for a small (internal or external induced) current to flow. That is a different connection scheme from the floating shield, or 1 point type of shielding strategy that we all have used for a long time. Is it shunting/shorting what is causing the effect? Is it the breaking of the leakage current between components? Is it reduced antenna effect, is the RFI trapped in the loop? Is the shield charged by the small electric current and therefore acting as a better kind of shield? I am also interested in good answers, as I like explanations myself, but for the moment I am happy fiddling around.
Saying this is a forum is correct, but I am not obligated to have a discussion nor answering questions from anyone who make subjective remarks a lot of the time (connector a, plating b, cable c etc..).
Cheers Juut
Your hypothesis is as good as any.
You don't need a White-Paper or Peer-Reviewed scientific evidence supported by an elite group of scientists, along with published peer-reviewed journals.
If it works it works...30% of men respond to a placebo vs Viagra, can't tell those 30% the wood isn't real.
If it works it works.
I've experimented with various things over the years, some with very positive results. I don't even bother to share, due to all the negativism...I just enjoy it myself and move on.
Dynobots Audio - Music is the Bridge Between Heaven and Earth
Where can I buy those placebo pills!
A Foolish Inconsistency Is The Hobgoblin Of Little Minds- Alfred E. Neuman
This is also appropriate for the Audiophiles...seeking improvements
LOL!!
The Internet[s]
Dynobots Audio - Music is the Bridge Between Heaven and Earth
Edits: 10/19/20
Juut,
This is an audio forum where matters like this are discussed. I'm not trying to personally give you a hard time, I'm questioning a tweak that is said to be an effective Faraday cage. A Faraday cage is already effective. I'm not one to hold a banner of science up in the air since I tend to be a subjectivist, but to postulate that a conventional Faraday cage is not effective, and that the notion of a closed loop was somehow missed by electrical engineers for many decades now is an extraordinary claim. If you would rather not discuss the matter, that is your prerogative.
Maybe someone else will take a look at the claim. Have a nice Sunday, too.
Cheers, Duster
It seems Dueland implements the oil in order to make the cotton less permeable to air. However, hydrocarbon lubrication oils have a dielectric constant from 2.1 to 2.8 which is just as much or higher than a solid (not foamed) polyethylene dielectric. It would be interesting to know what the dielectric constant of their oil impregnated cotton insulation is vs. Jupiter's non-oiled cotton insulated wires.
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