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Buddha
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Really dumb cable question.

Aloha,

Apolgies for my lack of insight, but what would happen to a cable that you decided to modify from the outside by wrapping it with different things?

Could you wrap a power cord or audio cable in tin foil and "shield" it?

Would that create inductance inside the cable?

Could you wrap it in a nonconductive material and change any characteristics?

How about wrapping it in that black electrical tape?

Could you dip it in latex that's been mixed with sand to dampen it from physical vibrations?

I've heard about putting CD's in the freezer, anybody try that on cables?

Could you drop them into liquid nitrogen and change them?

Run your cables through PVC conduits to keep out the light?

Are there any cable "mods" you do?

(Monty! I went to those sights you mentioned, but they didn't really get in to after-market mods...thanks again for those links on the other thread,)

Jeff Wong
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Re: Really dumb cable question.

Buddha - I made a post at another forum that covers your question about cryogenically treating something:

http://av123forum.com/showthread.php?s=&threadid=9686&perpage=15&pagenumber=11

I might have some thoughts on some of your other thought experiments and may post later. I need to step out and take care of some things.

Monty
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Re: Really dumb cable question.

Those aren't dumb questions! Those are natural extensions of what the cable guys constantly consider in the development of better cables.

If you consider the primary considerations of a cable design to be low capacitance and low inductance and that by lowering one you often increase the other, you can appreciate them tyring to achieve the best balance through the various designs.

I think the size of the conductor is the primary signature that a cable will impose on any system, which is basicly what bi-wiring attempts to achieve. This, more than anything else will determine the capacitance and inductance of a cable. After that, I think the dielectic becomes the consideration. Dielectic simply stores energy and releases it out of phase back into the system creating unwanted distortion. This is why the cable guys experiment with material that absorbs as little energy as is practical and why dbs battery packs in cable might be of great benefit...especially in tube gear that for obvious reasons isn't left on continually.

All those things you mentioned could create audible differences for various reasons. Wrapping cables with black tape for example could increase the dielectic nasties by storing more energy to later be released. This is basicly why cable guys recommend keeping your cables off of synthetic carpeting, you're just increasing the dielectic. This is also why pvc is avoided in better cables and why teflon is prefered. This is also why they strive to achieve as little contact between the conductor and the dielectic material as possible. Remember Tara Labs "Air Cables?"

The material used for the conductor also has certain properties that effect capacitance and inductance. Silver is ever so slightly a better conductor, but not by that much.

As for any mods that I do, I can't say that I do. However, I do use soft copper spades that can be easier to achieve a gas tight connection. I have tried the Radio Shack wire in various configurations, twisting, doubling and spreading, for example. I am also going to be trying out the RCA caps for the unused inputs on my gear to see if that does anything to remove noise.

Someday, cables are going to come with a list of specifications and gear is going to come with a recommended list of cable specifications. Instead of trying various cables in your system, you just might go to your favorite hi-fi shop and say, "I need an 8ft. run of .37 capacitance and .45 inductance cable, in mauve."

Jeff Wong
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Re: Really dumb cable question.

Monty has summed up very nicely what I would've mentioned about dielectric. I am not a very big fan of cables using PVC for this reason (music often sounds smeared with cables that use it as a dielectric.) This was a concern of mine when I was considering buying PS Audio's xStream Statement power cords; these cords use a sheath of PVC that is impregnated with ferrite (a slurry of ground ferrite is mixed in with the molten PVC during manufacture) to help reduce noise. Paul McGowan reassured me that they too at PS Audio were concerned about this and kept the PVC sheath far enough away from the conductors (sporting good dielectrics) not to have ill effect. Judging from the results of these cords in my system, I believe he and his team got it right. This may also be less of an issue with power cords. The times I've found PVC most objectionable soundwise was with interconnects or digital cables.

Years ago, I've tried making my own I2S cables, and let me tell you... working with aluminum foil is a waste of time. It's too thick and stiff to work with, and is nearly impossible to solder properly for grounding.

I think black electrical tape may be made from PVC, so I wouldn't recommend its use. I'd avoid the PVC conduits for the same reason, but this may not have horrible effects if the conductors aren't too close - The PS Audio cords don't appear to suffer from the relatively close proximity, but then again, the benefits of the use of the ferrite the whole length of the cord might outweigh the detriments of the PVC being near the bundles of wires that make up the cord.

Editor
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Re: Really dumb cable question.

Years ago, I was arguing about cables with a friend of mine, who was later to become editor of the English magazine Wireless World. He was dissing audiophiles' obsession with cables and cable dielectrics as nonsense. Would have use a capacitor with a PVC dielectric, I asked? Of course not, was his reply. PVC's a polarized delectric; its electrical properties are dreadful. So why then, I responded, are you not bothered by using a PVC-wrapped interconnect, which is just a long, stretched-out capacitor?

John Atkinson
Editor, Stereophile

Jeff Wong
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Re: Really dumb cable question.


Quote:
So why then, I responded, are you not bothered by using a PVC-wrapped interconnect, which is just a long, stretched-out capacitor?

I find it puzzling that some people won't stretch their imaginations a bit to see the logical extreme of something they're clearly aware of under narrower circumstances.

CECE
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Re: Really dumb cable question.

DC resistance is the major parameter for speaker cable, current needs copper, capacitance and inductance are non issues in speaker wire. It's audio freq, no micro RF or any other freq of the spectrum. DC resistance effects damping, control of the drivers. That is audible. Mystical cable parameters made up by ad mangers are irrelevant, inovative drawings and made up nonsense, about electrons jumping, ouncing, sticking is ad manager science. A cable designed for hard usae as in live venues, and other such physical propertys matter, depends on use. that's why there are differetn insulation types.

CECE
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Re: Really dumb cable question.

Do you really beleive you can HEAR the difference in a piece of wire wrapped in black electrical tape, 3M has different colors, would that also have an effect and one not wrapped? You have to tell me what kind of system you have that THIS changes how it sounds!!!! Do the color of the "wire nuts" change the sound, since "audio grade" wiring devices have an effect according to certain people with some incredible hearing abiltys? When does this begin to become absolute nonsense? Oh, I got my latest issue, time to go get some laughs for the day. Gotta read about some $20,000 3W amplifier, with "golden rule" 1.6 ratio blah blah blah magic twists in it's cover mounting screws, that are aligned with teh earths magnetic field to lower the noise floor, and I think an AC line cord with Otter skin insulation.

eagle
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Re: Really dumb cable question.

Wrapping any cable in tin foil MIGHT make a difference, but only if it is grounded to only either the source or destination device. Some cables are directional because the have shielding on them. The directionality is because the manufacturer wants it grounds at one particular end. I have some monster cables like that, but off hand I don't know which end goes where. The cables are in storage right now, so I can't tell you. Sorry.

Actually, metal "duct" tape would be better, I think. It would stick to the cable, where the foil wouldn't.

Anyway, wrap the cable in the foil/metal tape and attach a wire at one end. Connect this wire to the device and try it out. Try again connected at the other end. Decide which sounds better and stick to it.

In the case of the power cord, when connecting it at the a/c outlet end, connect the wire to the screw holding the cover plate on.

Windzilla
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Re: Really dumb cable question.

Ok, so I live right near a radio broadcast tower. When using my turn table, I could actually hear radio broadcasts if the needle was off the record. diligent experimentation leaves cables as the primary source of this disturbance. Wrapping my RCA cables in aluminum foil eliminated the radio from one speaker, and reduced the RFI in the other channel to some incoherrent noise.

so the foil works to reduce the interfearence from RFI, unfortunatelly it also decreases the GAF.

(my cables are blue-jeans cables basically some beldin/canare RCA deals, or a set made by an electrical engineering/audio file friend of mine, ive tried them both.
my TT is a thorens td126 mkiii with grado green cart. the pre is the bellari tube deally, and the amp is a kav-300i, L series or whatever)

eagle
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Re: Really dumb cable question.

You did ground the foil at one end or the other? Did one end work better than the other?

I'd guess that if you still have the problem only in one channel that there is another problem somewhere else.

Monty
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Re: Really dumb cable question.

Try running your phono preamp on another input at your Krell. I would slide it down away from any other used input and try a couple of those Cardas RCA caps on adjacent, unused inputs. I would also experiment with moving the phono pre around and away from the other gear...especially the pre power supply.

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