I can't even begin to speculate on why they would put that 10KΩ resistor into the cable. There is no design reason that I am aware of for an RS-485 data cable of short length (<10') to have such a resistor between the center conductor and the shield. The actual termination should be in the range of 75Ω to 120Ω. My personal opinion is that you have been fleeced, but I understand the need for audiophiles to believe in certain types of magic. If you consider yourself a dedicated audiophile then I am the wrong person to advise you.

 

I can't even begin to speculate on why they would put that 10KΩ resistor into the cable. There is no design reason that I am aware of for an RS-485 data cable of short length (<10') to have such a resistor between the center conductor and the shield. The actual termination should be in the range of 75Ω to 120Ω. My personal opinion is that you have been fleeced, but I understand the need for audiophiles to believe in certain types of magic. If you consider yourself a dedicated audiophile then I am the wrong person to advise you.

The weird thing is that the resistor was hidden from the user so there is not even a marketing benefit.

 

The weird thing is that the resistor was hidden from the user so there is not even a marketing benefit.

Maybe it is to ensure plausible deniability if anybody ever calls them out.

 

Ok some more information seems like this is a pull-down resistor:

Pull-down resistors are also used on outputs to provide a known output impedance.


Read more http://www.resistorguide.com/pull-up-resistor_pull-down-resistor/

Don't think there is anything nefarious about the design.

 

Ok some more information seems like this is a pull-down resistor:

Pull-down resistors are also used on outputs to provide a known output impedance.


Read more http://www.resistorguide.com/pull-up-resistor_pull-down-resistor/

Don't think there is anything nefarious about the design.

I have to admit, I think we are having fun poking at the idea of a $600 cable (that you bought for $225).

 

I have to admit, I think we are having fun poking at the idea of a $600 cable (that you bought for $225).

Ok now I know the cable is fine its time to attach those magic crystals to it. . By the way this cable is not worth £400, sounds exactly the same as my £90 digital cable.

 

Papabravo my other coax cable from Chord does not have any resistor between the ground and signal and has been working fine. I understand your point about keeping the potential the same at both ends then why don't we see this as a common design feature in all coax cables? The only difference between the Chord and Tellurium is that one has a plastic outer plug and the other has metallic ones.

I don't think it is possible to get inside the mind of the designer to know what he was thinking. It seems that the resistor in this application provides very little in the way of real benefits, especially considering the receiver undoubtedly has a low value termination resistor across the differential inputs.

 

Pardon my ignorance. How do you tell the source end from the receiver end on that cable?

 

So with this particular coax cable I am having frequent audio dropouts, triggered by other equipment switching on/off in the house. An ideas as to why this might be happening?

 

Inadequately filtered power rails in sender or receiver, causing loss of sync? Ground bounce?

 

Inadequately filtered power rails in sender or receiver, causing loss of sync? Ground bounce?

So how do it check if its the receiver of the sender. The sender has been earthed to the chassis and the receiver is properly earth with a third pin. My concern is that somehow the coax is picking up some AC being leaked into the chassis. I have checked the voltage between the coax ground on the sender chassis to earth but there is no potential difference.

 

So on the most sensitive AC scale you measured no voltage between the disconnected cable ground and the chassis?

 

Yes...

 

Well I know that AC is leaking into the chassis. But it must be in mV as I am unable to measure it with my basic multimeter. It then is travelling via the coax wire to the receiver(3pin). I can feel the charge on the chassis but as soon as I plug the receiver (3pin) in to the socket the charge is gone.

 

I can feel the charge on the chassis but as soon as I plug the receiver (3pin) in to the socket the charge is gone.

Don't like the sound of that .

The sender has been earthed to the chassis and the receiver is properly earth with a third pin.

If you're feeling a charge flow then something seems fishy with the earthing arrangement.

 

Is there an optical digital connection (Toslink) on the two devices?

 

Yes I have decided to go via Toslink. Even though the audio quality is not as good as a coax. But I would much rather protect my Dac/Amp from further damage. Think I will buy a better multimeter to see how much charge is actually leaking into the chassis. A bit too late now as the damage is already done.

 

Yes I have decided to go via Toslink. Even though the audio quality is not as good as a coax. ............

Sounds like another audiophile old-wive's-tale.
They both carry the same digital signal so the sound will be the same.
And that sound has nothing to do with "digital jitter" or other supposed digital signal degradation.
A digital signal is either perfectly received or it doesn't work.
Any jitter or other degradation is removed at the receiving end where a stable clock reconstructs the signal.

 

If you could feel a charge, a tingling, I wouldn't worry about that cable right now.

If someone is standing in water or touching a well grounded object(even just being barefoot).........one might get more than a tingle.

Something is not getting returned somewhere.

Start with your AC receptacle.

You have not stated your location.

 

I am in the UK. Opened the case yesterday and measured the ground from the chassis bolt still nothing. This is a Pioneer N50A unit maybe a couple of months old. Will look at the AC receptacle and make sure the wires are properly connected. Thanks