Same here. At some point I realized that single ended connections are just inviting trouble. Running the signal return along with the shield current is a poor idea at the best of times. Also, the RCA connector was invented as a low-cost way to connect consumer equipment. Even for a single ended connector it's not a good design.
Any two pieces of equipment connected together with a cable whose shield is earthed to their chassis will almost inevitably cause shield current. As well, anything picked up from the air will be on the shield as it flows to ground. There is some good reading here on good engineering practice for low noise systems:
http://www.diyaudio.com/forums/tubes-valves/246865-lets-talk-about-grounding.html
I'm not sure I understand that question. EMI gets picked up by any conductor in its field, causing current to flow. That current in the case of a single-ended connection is also flowing on the signal return. The suggested reading in the link explains all of this much better than I can.
Shielding works in two ways. Reflection loss and absorption loss. With reflection loss, the interference just bounces off the shielding. Absorption loss is due to eddy currents within the conductor serving as shielding. So I don't see how either of these end up going to ground.
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Not to put too fine a point on it, but your understanding of shielding has some holes in it.
Brittleness after the tight wrapping I was told. Funny thing our tech inadvertently cryo treated all the wires, he stripped them by dipping the ends in liquid N2 and cracking the insulation.
he meant probably fact when two appliances connected together, but there is some slight difference in potential
so then current flows tru shield making magnetic coupling to inner wire, etc
transported signal being modulated this way
For electric fields it's as simple as it seems: an electric field can't penetrate a closed conducting surface. This is known as Gauss's flux law; the closed conductive surface is a Faraday shield. For magnetic fields, the impinging field causes current to flow in any continuous conductor, the direction and magnitude of the current tending to generate an equal but opposite magnetic field that cancels the impinging field. The shield surface carries those currents.
Since a radio wave (say, from EMI in the environment) consists of a propagating electric field with a magnetic field at right angles to it (so-called Poynting vector), a shield has to shield both the electric and magnetic fields to be effective.
Electromagnetic shielding - Wikipedia, the free encyclopedia
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Solve one problem, cause another. Solder cold flows under pressure. Assuming that the wires are fastened under screw terminals, you need to regularly check the tightness.
I tried tinning the ends of speaker cables with solder but they kept coming loose. Then for quite a number of years I soldered banana plugs on the ends.
Nowadays I'm getting fat & lazy, I just use banana plugs which have twin grub screws to clamp the wire.
Spring loaded binding posts are so 1980s 😀
Nowadays I'm getting fat & lazy, I just use banana plugs which have twin grub screws to clamp the wire.
Spring loaded binding posts are so 1980s 😀
"Regularly" meaning maybe every few months., no worse then unsoldered wiring in my experience. A lot better than letting bare copper wiring corrode.
Funny, I have tinned leads under terminal strips that last for decades. In the computer industry, we high pressure crimp ring lugs on the end and that is what we put in the terminal strip. In a class from AMP, they showed how this was basically a cold weld and was stronger, lower resistance, and more tolerant of flex than hand crimp and solder. Believe me, when you are sending 80 amps through a terminal, resistance does matter, not like in a simple speaker cable. Banana jacks are for test equipment.
The very best speaker termination is the very cheapest. Solder the cable to the crossover board and run it out a sealed hole in the box. The best connector is no connector.
You can compensate for cold flow with a bevel washer stack. OOPS, that means adding steel washers to the magically pure environment. Silicone bronze?
I have an idea for product marketing. Brand a dialectic grease ( petroleum jelly for instance) as "Snake Oil". Sell it to prevent connection degradation. The irony is that it actually is a viable solution. This is how the phone company maintains quality low voltage connections on bare copper. This is why modern cars can sit a week and still start buy my TVR wouldn't.
The very best speaker termination is the very cheapest. Solder the cable to the crossover board and run it out a sealed hole in the box. The best connector is no connector.
You can compensate for cold flow with a bevel washer stack. OOPS, that means adding steel washers to the magically pure environment. Silicone bronze?
I have an idea for product marketing. Brand a dialectic grease ( petroleum jelly for instance) as "Snake Oil". Sell it to prevent connection degradation. The irony is that it actually is a viable solution. This is how the phone company maintains quality low voltage connections on bare copper. This is why modern cars can sit a week and still start buy my TVR wouldn't.
True, that's when I started machining my own from solid brass. (but a mere spring washer can do wonders for a standard binding post)
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