[sbelyo]

I want to make a shielded interconnect ans I saw that you terminate one end of the shield only to ground. Is this correct.

I make all my cables unshielded or without the shield connected to anything and I get some hum from one of the xformers on my tube amp. I just wanted to see if shielding it will make a difference.

 

[FallenAngel]

That's a little ambiguous and depends on the configuration of the cable to begin with. If you're using coaxial, you use the shield as it's the only ground you have. For other cables that have separate signal / ground wires plus a shielded, it was recommended to terminate the shielding to ground on the SOURCE end.

Yes, shielding the cable should make the hum go away when you're running a wire beside a transformer.

Good luck.

 

[hoosterw]

Quote:

Originally Posted by sbelyo /img/forum/go_quote.gif I want to make a shielded interconnect ans I saw that you terminate one end of the shield only to ground. Is this correct. I make all my cables unshielded or without the shield connected to anything and I get some hum from one of the xformers on my tube amp. I just wanted to see if shielding it will make a difference.

If you have a shield available I would always connect it, and yes one sided only.
Never two sided because that can create groundloops which will only be worse.

If the cable is the problem of the hum then it will surely help. Hum might also have a different reason for its existence.

Did you check the polarity of all your equipment when connecting to the mains?

Rgds

Hans

 

[sbelyo]

Quote:

Originally Posted by hoosterw /img/forum/go_quote.gif If you have a shield available I would always connect it, and yes one sided only. Never two sided because that can create groundloops which will only be worse. If the cable is the problem of the hum then it will surely help. Hum might also have a different reason for its existence. Did you check the polarity of all your equipment when connecting to the mains? Rgds Hans

I'll connect one end only to ground then.

That's a good question about mains polarity. I have a feeling that the wiring in my house is not correct and that may be the source of my problems.

How does one check?

 

[kingsqueak]

For about $10 at Home Depot you can pick up an outlet tester.

I was trying to find a pic online but couldn't.

They have a three prong plug on one end into a block of plastic with lights on the back side. Basically they light up if the outlet is live and give a color code to indicate if polarity and ground is correct.

 

[werdwerdus]

Just happened to have one less then 15 feet from me...
anyway, this is what it looks like

 

[sbelyo]

I've got one of those. Now I'm certain it will produce a bad result because my UPS for my pc says there's a wiring fault.

I'll test it and post the result.

 

[kingsqueak]

If the lights show that all the components are there, that there is a ground and maybe polarity is off, that's an easy fix.

If ground isn't there, it gets more complicated. Though it could just be that it wasn't secured to the outlet well, or wired sloppily.

If you test around your house and find ground or polarity fouled up in many places, you should really have a guy out to straighten you out.

 

[sbelyo]

It says Hot/Neutral Reversed

I'm guessing that means the white and black are wired backwards?

What effect would that have on my amps when I'm listening?

 

[sbelyo]

I finished a pair of shielded interconnects. Solved all my problems, absolutely no hum or noise at all.

I used Kimber twisted pair ofc stranded copper (Looks to be about 20AWG)

Very Nice and solid metal no name rca's from the local electronics store

I shielded the kimber with shielding from canare starquad and then covered it with 1/8" techflex

They are by far the best sounding pair of cables I've made so far

 

[warrior05]

congrats! now how about a pic before someone yells that this thread is worthless without pics!

 

[werdwerdus]

 

[sbelyo]

fair enough.... wait till I get home