RCA + Cable Soldering

[tiger0691]

This is how I am doing.

 

[jls001]

Black + Shield must be at source end.

If there is printed label on the jacket of the cable, direction of print is usually direction of draw of cable. So use starting end of label as source, and end of label as destination/amp. Many people believe making the signal travel in the direction in which the conductor was drawn sounds best. YMMV, of course, but I'm suggesting it since you are already making 'directional' cable.

 

[tiger0691]

Black + Shield must be at source end.

If there is printed label on the jacket of the cable, direction of print is usually direction of draw of cable. So use starting end of label as source, and end of label as destination/amp. Many people believe making the signal travel in the direction in which the conductor was drawn sounds best. YMMV, of course, but I'm suggesting it since you are already making 'directional' cable.

My case is little different. (one point earthing)

1. Source(DAC) : 2 pins Power Cable
----RCA Cable---- earthing to Pre Amp

2. Pre Amp : 2 pins Power Cable
----RCA Cable---- earthing to Power Amp

3. Power Amp : 3 pins Power Cable
---- earthing -----

In this concept, my RCA cables have directions (Source to Pre to Power)

Do you have better idea? I need your advice..............

 

[Thad E Ginathom]

Many people believe making the signal travel in the direction in which the conductor was drawn sounds best.

Actually, probably very few people believe such things. But very few is enough for the cable companies hyeah:

What is the technical implication of the shield being only attached one end. I know that this is sometimes done to avoid ground-loop hum, but surely the shield is compromised?

What I'm suggesting is that end-to-end is correct, and should only be compromised if it solves a larger problem of ground-loop hum. What are your thoughts on this?

I have a couple of thoughts on wire drawing, but they would be offtopic.

 

[jls001]

Disconnecting shield at destination avoids ground loops. For most people, ground loops and the resultant hum is fortunately never a problem, but for those unlucky to have it, this is one way of avoiding it. If there are other benefits, I'm not aware of any. I had read somewhere that some equipment OEMs follow this wiring convention even for internal signal wiring.

 

[tiger0691]

Actually, probably very few people believe such things. But very few is enough for the cable companies hyeah:

What is the technical implication of the shield being only attached one end. I know that this is sometimes done to avoid ground-loop hum, but surely the shield is compromised?

What I'm suggesting is that end-to-end is correct, and should only be compromised if it solves a larger problem of ground-loop hum. What are your thoughts on this?

I have a couple of thoughts on wire drawing, but they would be offtopic.

I agree with you. For me it works well.

 

[jls001]

My case is little different. (one point earthing)

1. Source(DAC) : 2 pins Power Cable
----RCA Cable---- earthing to Pre Amp

2. Pre Amp : 2 pins Power Cable
----RCA Cable---- earthing to Power Amp

3. Power Amp : 3 pins Power Cable
---- earthing -----

In this concept, my RCA cables have directions (Source to Pre to Power)

Do you have better idea? I need your advice..............

If you want to have a single point of earthing, do it at the power amp. Don't ground DAC and Pre. But do understand that some equipments are wired for 3-pin power connection, while some are designed for 2-pin power connection (like the Marantz CD6003 whose IEC socket does NOT have earth pin, though the supplied power cord is a regular 3-wire cord). So you could be compromising on safety somewhere.

At one point, I followed the above method in my setup. I took out the ground pin connections on the pre and phono pre. My CDP has a ground lift, so I used that too. Grounding only in the power amp. Honestly I don't know if that had helped or not. I keep swapping power cords so I don't know what is grounded and what is not, at this time

If any device is suspect, you can cheaply make a ground isolation circuit using a 10A rectifier with two 10A/10 Ohms thermistors (parts cost will be less than Rs 100). I use it for my Pass Pearl II phono pre's outboard power supply.

 

[saheb11123]

Would you elaborate please ?

 

[keith_correa]

Disconnecting shield at destination avoids ground loops. For most people, ground loops and the resultant hum is fortunately never a problem, but for those unlucky to have it, this is one way of avoiding it. If there are other benefits, I'm not aware of any. I had read somewhere that some equipment OEMs follow this wiring convention even for internal signal wiring.

IMO, this only works for balanced connections. For unbalanced, I doubt it does any good/harm.
The way I would do it is to to draw out a wire from -ve at both the RCA plug ends and from both the shield ends. I would use some sort of connector [crude: alligator clip!] mating to connect/disconnect them both and thus would have the flexibility to try different options at will.

 

[tiger0691]

If you want to have a single point of earthing, do it at the power amp. Don't ground DAC and Pre. But do understand that some equipments are wired for 3-pin power connection, while some are designed for 2-pin power connection (like the Marantz CD6003 whose IEC socket does NOT have earth pin, though the supplied power cord is a regular 3-wire cord). So you could be compromising on safety somewhere.

At one point, I followed the above method in my setup. I took out the ground pin connections on the pre and phono pre. My CDP has a ground lift, so I used that too. Grounding only in the power amp. Honestly I don't know if that had helped or not. I keep swapping power cords so I don't know what is grounded and what is not, at this time

If any device is suspect, you can cheaply make a ground isolation circuit using a 10A rectifier with two 10A/10 Ohms thermistors (parts cost will be less than Rs 100). I use it for my Pass Pearl II phono pre's outboard power supply.

Even though my dac and pre amp have 2 pins power code(no ground, it has three wires but ground wire is not used),
they are connected through RCA cables to Power AMP
allowing the leaking current to go out though power amp(single point)
This is my simple calculation. - approved by no one -

 

[jls001]

Would you elaborate please ?

If you're referring to ground isolation please check the diagram I had posted here: http://www.hifivision.com/diy/46286-another-pearl-2-buiild-3.html

 

[Thad E Ginathom]

I have just been browsing Beleden to see what I could learn. Of course, this means getting interested in and reading about a dozen things --- but here is an interesting article about ground loops and the effects of cutting shields. I'm not sure if that "creates a HF filter" thing refers to our unbalanced interconnects or to balanced cable...

Ground Loops (Belden)


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