Chord DAC and Naim Compatibility Issues?

No. Naim leads are for the most part non shielded. And I still find a power cycle of the power amp once every few weeks puts the zing back.

I did run into the same mains buzz issue once with Hugo/SN2 while only additional source was Rega P3 into Stageline. Being in contact with Chord they provided some instruction to eliminate this. It was necessary to ground the Hugo as source component for Naim expects it to be grounded. I did connect a earth wire from Ground Terminal on back of the SN2 to the earth pin of a mains plug, plugged into a free socket of my mains distribution block. The buzz was immediately gone.

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I think the problem is likely the non-shielded RCA cables. The much less expensive but shielded RCA’s do not hum.

Although it sounds like grounding the preamp also solved this issue for a few other members. I’m going to try and run a ground cable. If that doesn’t help then Kimber Kable can shield the cables.

I am not sure what you are meaning here… an ungrounded shield can be still effective as it can capacitively couple to ground, or even act as a reflector … but there is no known concept I am aware of a ‘saturated’ shield.

Grounding hums are typically produced when there is an inductive loop caused typically in a ground… and the stray electro magnetic field in your house, typically at mains frequency, induces a tiny voltage into this ground inductive loop, this causes an imbalance in the non balanced signal, and you hear this induced voltage as a hum.
If the loop is lossy then the induced voltage can be less and the induced hum less.

Another manifestation of induced loops with Naim, is the recommendation on some equipment of running the Burndy lead and digital power Snaic close together to reduce the overall cross section of an induced loop, thereby minimising any induced noise and lowering the noise floor.

Well Simon, I can only tell you what two electrical engineers told me (and I make no false claims about the fact I am absolutely not an electrical engineer). I can’t really argue or refute the point - I don’t have the knowledge background.

I was told by two different electrical engineers when discussing a shielded Luxman speaker cable with a drain wire, that a shielded interconnect or speaker cable does more harm than good if the drain wire from the shield is not earthed at one end. They both said a non earthed shield causes capacitance to go up (changing the intended characteristics of the cable) and that the shield itself is subject to saturation in the same way that a ferrite choke is when undersized. And therefore, to always choose an unshielded cable, or a shielded cable that you can guarantee is properly earthed.

The background being “What do I do with the drain wire on this Luxman speaker cable if I buy it for my new Luxman amp?” And the short version of their answers being “Earth one and or don’t buy it.

Ok doesn’t really make sense as described, it would be interesting to understand what they were referring to.
Capacitance effectively exists between two points with a gap between them, so it would be interesting to understand what they were wanting to describe. Clearly capacitance exists between conductors and a shield encompassing it irrespective of a drain wire. Without a drain wire, the shield is capacitively coupled, ie effectively a capacitor comprised from your environment
Think of the drain wire as effectively part of the circuit, with a capacitor between your active signal wire and the point your drain wire connects to your circuit.
The potential energy with capacitance is charge… and when it saturates it’s flashes over with a spark… ie the charge is too great for the dielectric between the two points… that’s how lightning works for example… it’s a long way removed from a signal interconnect however…and interconnects don’t bristle with crackling discharges.

But don’t get me wrong a drain wire can be advantageous, not least for safety, as it provides a low resistance or very low inductive impedance path to a point such as ground, as well conducting any induced external currents into the shield in relatively electrically noisy environments.
If the drain wire was not connected that path becomes a higher impedance to ground and would vary with frequency.

This is why there is usually advantages to true balanced interconnects as opposed to unbalanced typically RCA connections, where the hot and cold signal elements are separated from the shield and it’s connection to ground.
DIN can also allow a shield ground seperate from signal ground but for unbalanced signals.
However I would argue with unbalanced RCA (phono) connections you may find a floating shield or no shield advantageous in some circumstances depending on the design of the connected electronics. To my mind it’s definitely not a case of one size fits all.

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At the risk of steering this thread further from the actual specific topic, would you be concerned about a speaker cable with a drain wire was left unterminated at both ends? To be honest such cables are fairly rare in most parts of the world but the Japanese seem fond of them… and just about every single box (source, pre, power, you name it) has a chassis earth terminal. Of course, there is no ground earth here for the most part on the mains so a lot of high end gear simply has everything earthed to chassis and a lot of crazy makeshift earth arrangements like taking a lead from one chassis earth to a ground earth terminal usually in another room. Or more likely, simply not ground earthed at all.

I wouldn’t be concerned of such a speaker cable as such, but I guess it’s what it does to the cables characteristics that counts.
To my way of thinking, speaker cables are best kept as straightforward as possible
Simon

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