According to this article he's right Andrew.
http://www.diyaudio.com/forums/diya...udio-component-grounding-interconnection.html
Look at Section 3.2 Single Ended Interconnections : Grounding
Figure 3.2-1 shows the pin1 issue in single ended form.
There are actually a lot of articles on the internet which show single ended RCA connector body's grounded to the equipment chassis.
However this still presents the problem (in diy built components) of signal contamination from the noise on the mains earth. Numerous 'solutions' involving resistors or capacitors and even diodes don't get around the fact that mains earth pollution is far worse than RF pollution picked up by cables.
I've tried both ways and favour floating signal returns in my diy equipment, all of which has chassis connected directly to mains earth to comply with safety procedures and the law.
If I could legally build double insulated equipment I would most probably ground ALL returns to chassis like most commercial hifi equipment does. However to do so would cost me a fortune to have all the relevant testing carried out and certification awarded.
This is simply not an option for the diy builder.
The 'solution' to a single ended so called pin1 problem appears to be the use of isolating transformers which (for a decent version) is not cheap.
http://www.diyaudio.com/forums/diya...udio-component-grounding-interconnection.html
Look at Section 3.2 Single Ended Interconnections : Grounding
Figure 3.2-1 shows the pin1 issue in single ended form.
There are actually a lot of articles on the internet which show single ended RCA connector body's grounded to the equipment chassis.
However this still presents the problem (in diy built components) of signal contamination from the noise on the mains earth. Numerous 'solutions' involving resistors or capacitors and even diodes don't get around the fact that mains earth pollution is far worse than RF pollution picked up by cables.
I've tried both ways and favour floating signal returns in my diy equipment, all of which has chassis connected directly to mains earth to comply with safety procedures and the law.
If I could legally build double insulated equipment I would most probably ground ALL returns to chassis like most commercial hifi equipment does. However to do so would cost me a fortune to have all the relevant testing carried out and certification awarded.
This is simply not an option for the diy builder.
The 'solution' to a single ended so called pin1 problem appears to be the use of isolating transformers which (for a decent version) is not cheap.
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are you sure "he's right"?
That there is an equivalent to the Pin1 problem in a two wire connection system?
or,
that he should connect the Return to Chassis?
In both cases, my opinion and my interpretation, of that section I tend to disagree.
There is no Pin1 in a two wire system.
The Return should not be directly connected to Chassis.
The article shows a separate Chassis to Chassis wire for all nine of the diagrams.
Figure 3,2-1 The Pin 1 Problem In A Single-ended Connection.
What other meaning can I attach to that statement?
What other meaning can I attach to that statement?
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All I can do is to repeat frommy post #19:
Jim Brown writes:
The Pin 1 Problem: The most common way that hum, buzz, and RF interference enters equipment is via a design defect first widely understood by the pro audio community thanks to the work of Neil Muncy, (RIP).
He named it "the pin 1 problem," because it is a mis-wiring of the shield of audio cables – pin 1 in the XLR connector commonly used for pro audio, but it is just as much a problem in unbalanced interfaces of all types
Jim Brown writes:
The Pin 1 Problem: The most common way that hum, buzz, and RF interference enters equipment is via a design defect first widely understood by the pro audio community thanks to the work of Neil Muncy, (RIP).
He named it "the pin 1 problem," because it is a mis-wiring of the shield of audio cables – pin 1 in the XLR connector commonly used for pro audio, but it is just as much a problem in unbalanced interfaces of all types
http://www.hottconsultants.com/pdf_files/Audio Interconnections.pdf
http://www.hottconsultants.com/pdf_files/aes-2007.pdf
Hum problems can often be solved by adding nice thick low resistance wires between chassis, providing a low resistance connection in parallel with the single ended screen.
http://www.hottconsultants.com/pdf_files/aes-2007.pdf
Hum problems can often be solved by adding nice thick low resistance wires between chassis, providing a low resistance connection in parallel with the single ended screen.
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'marce' your first reference paper is 6 pages long, the second reference PowerPoint is 40 slides long.
Which section of each?
Which section of each?
All of it is relevant 🙂
One of the main problems with single ended interconnects though can be the shield resistance, hence my comment about a thicker low resistance cable in parallel between the two chassis, it can often break a larger loop formed by the PE connections through the mains leads.
Now I am going to relax after a hard weekend driving round relatives!!, alcohol and music are on the cards
🙂
One of the main problems with single ended interconnects though can be the shield resistance, hence my comment about a thicker low resistance cable in parallel between the two chassis, it can often break a larger loop formed by the PE connections through the mains leads.
Now I am going to relax after a hard weekend driving round relatives!!, alcohol and music are on the cards
🙂
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