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Post by Deleted on Mar 10, 2022 10:10:48 GMT
Why has the trend in cables drifted away from a coax cable, towards a twisted pair with a shield?
What is the benefit of a twisted pair with a shield connected at one end?
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Post by firebottle on Mar 10, 2022 10:28:07 GMT
The twisted pair uses the same type of conductor for both signal and return so has an advantage from the start.
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Post by Deleted on Mar 10, 2022 20:53:13 GMT
One of the reasons I asked the question is that some people believe that coax is best for an unbalanced interconnect. Other believe that there is no difference between cables.
I wish I could put myself in the latter group, as it would save me a fortune.
The only coax I have handy (apart from AC110 I have just remembered about) is some Webro WF100 tv cable, so I knocked up a cable with a length of this.
I want it to sound as good as the Neotech OCC cable. But it does not, to my ears. It sounds less “open” and less detailed. Some will say that this is because the shield is connected at source end, and this is dragging RF interference into the source.
I am disappointed.
An interesting experiment at the bake-off would be to do a “blind” cable test, where someone changes the cables, and is the only one who knows what is what, and the others have to guess what the cable is.
I tried this, but it was I possible, as I need to see what I am doing.
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Bigman80
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Post by Bigman80 on Mar 10, 2022 21:02:24 GMT
One of the reasons I asked the question is that some people believe that coax is best for an unbalanced interconnect. Other believe that there is no difference between cables. I wish I could put myself in the latter group, as it would save me a fortune. The only coax I have handy (apart from AC110 I have just remembered about) is some Webro WF100 tv cable, so I knocked up a cable with a length of this. I want it to sound as good as the Neotech OCC cable. But it does not, to my ears. It sounds less “open” and less detailed. Some will say that this is because the shield is connected at source end, and this is dragging RF interference into the source. I am disappointed. An interesting experiment at the bake-off would be to do a “blind” cable test, where someone changes the cables, and is the only one who knows what is what, and the others have to guess what the cable is. I tried this, but it was I possible, as I need to see what I am doing. These is an obvious difference with cables. No blind test required. However, I'm happy to throw a spanner in the works at the Bakeoff and change a cable for the general listeners and see if they hear a difference. Just to see if it's different or the same I suppose would be enough. I won't tell them if I've swapped or not. Coax hasn't been great for audio in my system. That's why I dont use it. Twisted pair in a braid is always better IME. Coax can also be mega microphonic.....no idea why. I only ever use it if I absolutely have to. |
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Post by Deleted on Mar 10, 2022 21:08:49 GMT
Coax is supposed to have better “noise rejection”than a shielded twisted pair.
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Bigman80
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Post by Bigman80 on Mar 10, 2022 21:30:19 GMT
Coax is supposed to have better “noise rejection”than a shielded twisted pair. Why? |
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Post by sq225917 on Mar 10, 2022 21:51:02 GMT
In a balanced system twisted pair can reject almost all the noise, only not hitting 100% due to inaccuracies in the twist. In a SE twisted pair connection one wire goes to ground so there's close to zero reduction in noise pick up on the signal wire.
In a SE coax connection you can at least shield the signal wire partially and shunt the noise to gnd off the braided shield. The higher the coverage of the shield the better the rejection.
A SE twisted pair is NEVER better at rejecting noise than coax. But that's not to say you have any noise that needs rejecting anyway.
That one prefers the sound of a twisted pair SE wire over a coax, is down to taste, bias etc and not reflected in noise measurements between coax and twisted. Because coax always measures better for noise rejection unless there's plenty additional, foil wrap etc shielding on the SE twisted pair.
Important to be very clear about real balanced (diffetential) signalling vs SE when discussing twisted pair.
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Post by Deleted on Mar 14, 2022 18:03:28 GMT
Another question. What is more important, the quality of the conductors, or the dielectric?
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Post by brucew268 on Mar 21, 2022 14:12:51 GMT
Another question. What is more important, the quality of the conductors, or the dielectric? I think this is a good question, though not sure how one would quanitfy it. For example, which would be better:
OCC wire with PVC insulation Basic OFC wire with solid PTFE
Or to put a finer point on the comparison--
OCC wire w/solid teflon (ala Neotech hookup) [prob not quite as good as either of the two above]
VH Audio says that solid fluoropolymers have a dielectric constant of 2.1 and a vacuum has 1.0. He claims his foamed Airlok has a constant of 1.4. though about 3x the price of Neotech hookup wire and 6x the price of the Triple-C.
But which combination wins out and how would one measure?
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Post by antonio on Mar 22, 2022 6:49:38 GMT
Bruce you have certainly put the 'cat among the pigeons' with that question. Since the Triple C is sold out, it may make it an easier buying decision.
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Post by brucew268 on Mar 22, 2022 8:56:43 GMT
Bruce you have certainly put the 'cat among the pigeons' with that question. Since the Triple C is sold out, it may make it an easier buying decision. It wasn't meant to be contentious. I buy that dielectric plays a role in cable sound and performance and also that the material/purity/crystal structure of the wire plays a role, and I don't assume that one completely trumps the other. But how to define the relative importance?
- When the Triple C hookup is in stock, it is a no brainer from any angle: wire, dielectric, cost.
- The Neotech OCC/Teflon is good but a pain to work with as it won't hold a bend or a twist and the solid teflon takes a long time to break in, though thin and well made.
- The VH Audio hookup seems like it would be rather good but absurdly expensive to ship here unless you know someone making a trip to America... and even then the wire is a bit expensive.
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Post by antonio on Mar 22, 2022 9:21:05 GMT
I never thought your question as contentious Bruce, but a good question, I am waiting to see what others think.
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Post by Deleted on Mar 22, 2022 9:40:54 GMT
The reason I asked the question was that using a balanced connection, there is a clear difference to me between the Neotech and Elecaudio cables.
My preference is the Elecaudio, which has a Teflon dielectric. Both are OCC.
However, on my analogue side, I am failing to hear the same type of difference between my Webro and the Neotech OCC.
This could be limited by the Mogami tonearm cable though. I will look at fitting an external RCA box, and use a quality coax cable.
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Post by antonio on Mar 22, 2022 16:52:01 GMT
It would appear we mess with cables when we have nothing else to mess with, Bigman's to blame  |
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Post by sq225917 on Mar 22, 2022 19:49:04 GMT
I used VH foamed fluropolymer on a tonearm. 10 silver in cotton wires in twisted pairs all identical for signal pos, neg and gnd wire. Signal wires went into four Foamed FP sleeves as did ground, 4 signal then encapsulated in copper foil, not tape, real foil, ext gnd sat outside this construct in a 98% braided screen. Cardas 90 degree socket and metal bodied eichmann.
It was massive, massively shielded, hugely awkward.
Sounded no different to a cheap starquad using braid as gnd.
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Post by brucew268 on Mar 22, 2022 22:03:51 GMT
I used VH foamed fluropolymer on a tonearm. 10 silver in cotton wires in twisted pairs all identical for signal pos, neg and gnd wire. Signal wires went into four Foamed FP sleeves as did ground, 4 signal then encapsulated in copper foil, not tape, real foil, ext gnd sat outside this construct in a 98% braided screen. Cardas 90 degree socket and metal bodied eichmann. It was massive, massively shielded, hugely awkward. Sounded no different to a cheap starquad using braid as gnd. Chuckle. That must have been rather disappointing. |
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