Yes. Exactly. The shield does not connect to ground at both pieces of equipment in this example.
Well, as far as I know with regard to RCA three wire/balanced cable connections it creates a Faraday shield with the "hash" picked up on the shield traveling harmlessly to the low output Z of the source component.
This is why you don't connect both ends of the sheild. Every DIY RCA cable I make is connected in this way.
This is the reason some cables actually have directional arrows on them.
If you're using a two conductor cable such as coax then of course you'd connect the "shield" at both ends. I'm not sure how much shielding it's doing acting as one of the conductors though.
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I make mine from bog standard coax. Given the spacer between the core and the outer shield is made up of a series of chambers I slide an additional wire down inside the coax. This gives me the core for RCA signal and the second wire for the outer RCA thingy )technical term). I then use the shield as a shield, running it to earth at one end (I used the amp for my earth). It seems to work well but I daresay that someone will tell me it's not right. It does mean you have a fairly rigid wire as it is solid core but I move my hifi once very ten years so not really an issue.
I think you are talking about something different in simply doubling up the earth connections, Geosto. You might like to consider the effect of increased capacitance there at 5m of nominal high impedance cable, and the difference with either arrangement of mic.cable especially.
As far as the signal is concerned, one strand in braid and wire will do the job. There is no benefit in having an earth any bigger than it already needs to be to cover the inner insulation, at 5 or so times c.s.a. of the "hot" wire.
Let's not try to do electronics by imagination, either. A little rationality will go much further toward a working, low noise result. When the desired end is a routine domestic audio connection of no great specification, I wonder where the waffle about shielded leads with silly arrangements is going.
Just wire it plain like any commercial cable, even the snake-oil $1,000 ones. If you have repeatable, better results on similar sub bass leads then post them. It's fine to substitute cables in a pinch but to try to wire them as something that can't be in a 2 terminal circuit is just audiophoolery.
As far as the signal is concerned, one strand in braid and wire will do the job. There is no benefit in having an earth any bigger than it already needs to be to cover the inner insulation, at 5 or so times c.s.a. of the "hot" wire.
Let's not try to do electronics by imagination, either. A little rationality will go much further toward a working, low noise result. When the desired end is a routine domestic audio connection of no great specification, I wonder where the waffle about shielded leads with silly arrangements is going.
Just wire it plain like any commercial cable, even the snake-oil $1,000 ones. If you have repeatable, better results on similar sub bass leads then post them. It's fine to substitute cables in a pinch but to try to wire them as something that can't be in a 2 terminal circuit is just audiophoolery.
Which, unsurprisingly, is electrically the same point as the earth of the receiving component. Where is the difference to the meaning "Faraday shield" if the earth connection is made via the shield, or at one end only, if not solely in the mind?
Nope, Originals (Hitachi, decades ago, were just snipped and common (chassis) earth return used. Most now do, as you indicate, to little or no benefit. How will a wire of say 3' shorting the common earth points, possibly restrict EMI received by the braid to the transmitting end? Both ends are electrically the same.
About the same amount of shielding as any part of the chassis, interconnec ts etc. in any unbalanced pro system, recording studios etc. Signals and interference are all referred to the same points and don't hide somewhere just because you used a plain wire and not the braid to make the circuit. Maybe at RF there is an effect or two but at 50 Hz with a nominal 47k impedance, you are, I hope, surely kidding 😀😀
This is a well documented practice.
If you don't understand it, I would suggest you research it for yourself.
Yep. RFI is dumped to lowest impedance (source) with little to no effect on the signal. Both ends are not the same if one end is left floating.
Look it up.
A good one is "Valve Amplifiers" by Morgan Jones. It is explained quite well there.
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hags, there are plenty of engineering references to cables, even commercial products as you describe when used as adaptors for balanced to unbalanced connections where shield roles are reversed for signal return. These make sense.
OTOH, there are also a few variations of unbalanced, single shielded types with severed earth braid connection schemes in mainly DIY form, different makers and boutique suppliers claiming alternate opposing views on which end the earth should be connected depending on the equipment and makers views. Then there are those like NP who feel that cable shields should be earthed both ends as best suits correctly designed and set up equipment. This concurs with mainstream audio engineering practice.
I have no argument with folks who want to play hi-fi through a light socket if it suits them but when it comes to advising newbs on appropriate wiring for standard subs with no high-end aspirations in an unknown system, I believe that basic, sound engineering practice is the only sane way to go. Short of gross hum and noise problems, if ever there is some esoteric nuance in bass to be gained from tinkering with earth connections for subwoofer frequencies I might gladly agree and make such cables and use them myself.
OTOH, there are also a few variations of unbalanced, single shielded types with severed earth braid connection schemes in mainly DIY form, different makers and boutique suppliers claiming alternate opposing views on which end the earth should be connected depending on the equipment and makers views. Then there are those like NP who feel that cable shields should be earthed both ends as best suits correctly designed and set up equipment. This concurs with mainstream audio engineering practice.
I have no argument with folks who want to play hi-fi through a light socket if it suits them but when it comes to advising newbs on appropriate wiring for standard subs with no high-end aspirations in an unknown system, I believe that basic, sound engineering practice is the only sane way to go. Short of gross hum and noise problems, if ever there is some esoteric nuance in bass to be gained from tinkering with earth connections for subwoofer frequencies I might gladly agree and make such cables and use them myself.
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I did not describe any commercial products. I am talking about DIY audio interconnects. I personally don't consider coax to be shielded as the ground is out there for the world to interfere with. RFI and "hash" is picked up on both conductors and has no where to go except into the audio circuit.
There are gobs of information regarding shield connection on an unbalanced audio interconnect. The concensus regarding unbalanced connection of a balanced cable, ie, a twisted pair with shielding, is to connect the shield to common/ground at one end only. That end should be connected to the low Z component, usually a source. It is common commercial practice to mark the cable direction based on this.
I agree, sound engineering practice is the only sane way to go. The correct way to connect a balanced interconnect, a twisted pair with shield, to unbalanced connectors, RCAs, is to connect the shield at one end only. This end is usually connected to the low Z component, usually a source component.
Again, I'm talking about common audio interconnects, balanced wire configuration, usually it's a twisted pair with a braided shield. The OP didn't mention any true balanced operation, in fact, he said ICs with RCAS. He was looking for information on DIY cables. Now he's got some.
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