I will have to experiment using my mobile phone, though it hasn't been interfering lately 
I've been using STP for my unbalanced connections with screen connected to signal return at the sending end. Interest in the Faraday cage just got me wondering.............For an extended discussion of Faraday Shields wrt audio cables, see:
DIY DC power cables - Page 9 - UpTone Audio (Sponsored) - Computer Audiophile and following.
What he is describing / advocating is NOT a Faraday Shield in any accepted sense.
The extra conductor will reduce the connection impedance - similar to the added conductors described in the link I posted.
The idea is that with low impedance the shield current becomes unimportant as it can only cause a correspondingly low voltage (thanks Mr Ohm) while SCIN noise is insignificant. All this assumes balanced connections.
But the post linked above misses several points eg Low frequency H fields pretty much go straight through cable shields - esp if non-ferrous (Cu / Al)
I think John Swenson's claims can be safely dismissed as nonsense, he mentions doing tests but I couldn't find any evidence of this or results. How running a wire parallel to the screen does anything other than reduce impedance is a mystery to me. Alarm bells also rang when he claimed screening against low frequency.
I'm not competent to comment on the points made (and rather wish I hadn't posted the link) but I can't let the above go without asking which of Swenson's designs (he's a designer, BTW, not a vendor) are "close to snake oil". As I hate wasting money on fakes, it'd be good to be warned.
Hopefully, Bill can let me know as quickly as he responded to my opening post.
UpTone Audio — Expertly engineered audio upgrades that deliver results Take your pick. I can't see anything there that is actually worth the money personally.
I'm glad you did, I wondered why no one challenged his claims, but then the fact that Up Tone Audio sponsors that forum is interesting too. One really has to be careful in this game
Yes. His idea of running an extra wire from one end of the shield to the other, but otherwise leaving it isolated is nonsense of the most pure kind. Clearly he is quite confused. He asks "So how come nobody does this?"; the reason is quite simple: it isn't true. He then goes on to talk nonsense about the ground wire for a turntable.scottjoplin said:
I would not buy anything from someone who is so confused about electrical basics.
This is from this article Design Techniques for EMC: cables and connectors linked to by billsherv :
Does this mean that the signal return would have some immunity to currents flowing in the shield even when they're connected together both ends?
Does this mean that the signal return would have some immunity to currents flowing in the shield even when they're connected together both ends?
Twisting cables minimises loop area. This is good.
Running return and send together is good from the point of view of keeping Kirchoff happy and trying to herd the return current via the same path.
Keeping return separate from PE is also good.
To do this may require some mods to the unit and may not cause an audible improvment but at least gives you the warm feeling of doing the best with what you have.
Running return and send together is good from the point of view of keeping Kirchoff happy and trying to herd the return current via the same path.
Keeping return separate from PE is also good.
To do this may require some mods to the unit and may not cause an audible improvment but at least gives you the warm feeling of doing the best with what you have.
H.Ott mentions adding a separate ground lead between chassis that are connected with a screen ground.
I can't remember the context, but I do recall that he advocates this impedance reduction method. I do recall a warning that the extra wire/cable MUST NOT contact the screen.
Quoted by scottjoplin:
This is only true for sufficiently high frequencies, where cable inductance dominates over cable resistance. Typically this means from 10's of kHz upwards, although some cable designs could push this down into the upper end of the audio band. At lower frequencies the return current divides according to resistance, not proximity to the forward current. In this case it is hard to beat the forward and return currents being concentric, as this renders the external coupling to be near zero.
Parallel Earth (ground) Conductor [PEC] is tested in detail here Bonding Cable Shields at Both Ends to Reduce Noise
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