Chord Ethernet cables

In both my first homes [in Herefordshire in the 1960s/70s], farmhouses on the end of miles of overhead three phase mains, the plumbing suffered from tap tingle!

I am very sensitive to electricity, and developed the technique of putting a towel on the floor when using the wash basin.

The HMV mono gramophone used to hum like a good one throughout as did the Stellar black and white TV. When the water heater kicked in the lights went darker, and more or less bounced back ...

How times have changed.

ATB from George

I think I must be really lucky - I'm on a PME system, but the PD from the Earth to the cold water system is typically only about 200mV.

Bizarre though that I'm the one with so much sound degradation if I feed my audio system with an unfiltered mains supply.  I know that they're not causally linked, but odd that it's so good in one way and so bad in another.

Now I definitely want to get a DSO / spectrum analyser, have a good look and find out what the reality is.  I'll give it at least a few more days though to allow my full mental faculties to return before I do anything more with mains voltages.

Huge, in your above post how are you determining your Earth potential? The plumbing is (should be)'bonded to your electrical safety earth, which of course can be at a somewhat different potential to your actual earth/ground potential at your property,if you have PME.

In other words the potential difference between your cold water pipe and the mains safety earth will be minimal assuming your safety earth is correctly bonded... 

Of course the other area that some get a little confused is thinking that safety earth sinks RFI.. It doesn't really, in fact with PME it can help conduct and share RFI from neighbours.

I do have RF grounding planes for other uses  and they are quite involved.. and of course the distance in terms of RF wavelength or multiples thereof between the device and the ground potential becomes critical for the effectiveness of the RF grounding.

Simon

Hi Simon,

It wasn't measured with any degree of rigour, just using a DMM between the case of an earthed appliance and a cold water pipe.

At the time I was primarily wanting to check the earthing of the appliance through that socket, so wasn't concerned with the accuracy.  I realised later that this was some distance from the main earth bond point, so could be subject to variance and a big inductance loop. I also wasn't careful about load.

The water supply here is all metal pipe and geology is limestone, so that acts as a fairly good local earth.  I'm well aware that RF doesn't behave as DC hence the earlier comment about causality.

Sorry I'm having difficulty explaining now, I'll try again later.

Huge no worries, just wanted to point out there should be minimal volts between your cold water pipe and electrical earth if all is well.. And that appears the case..

You take care, it sounds like you have been going through some ordeal.

PS sorry I am aware you know about RFI sinks. It was a more general comment for the forum in the context of earthed Ethernet leads and not specifically for you.. I should have been clearer.

Simon

That must be me ! (Not a little, and now even more...)

To keep this simple,  I will call the power supply protective earth “E”  & the water/gas pipe ground “GND”  

The NAS SMPS carries E thru to DC 0v  @ zero ohms.

(that was a surprise to me)

This DC 0v [E] is connected to the NAS port, then to the STP shield which carries thru the switch to the other STP to the NDX port which is also connect to E.

Therefore:  the NAS & NDX each have a direct E connection from the power supply and are additionally linked via the STP network to each others E. 

This does not constitute a ground loop, it is simply connecting & interconnecting E in two different circuits.

It is not a ground loop because the STP shields do not carry a signal; they are simply a conduit for the signal carrying TP’s.

I can see a potential problem if a LAN has components connected to two different power circuits, there might (will) be a potential difference between each of those circuits E.  I would be wary of connecting that potential difference thru the STP shields, it has a potential for noise at least.  I would install either a section of UTP to isolate the E link or a UTP connector or even an Ethernet isolator.

Fortunately my system has all the audio components sharing a common mains supply.  And with into info I have gathered over these last few days, I am not contemplating isolating anything or adding another ground connection at the switch to either E or GND.

Regarding the potential difference between E & GND, low levels are absolutely normal, my E to GND is 250mV with all the audio off,  it rises to a variable 380-420mV with it all on.

Re: the 0.03 amps I measured yesterday, this is very low level stuff that is shorted to 0 amps by touching both meter probes, so is nothing other than a static type of potential. 

Mike,

I also have my audio and network components connected to the same earth point (due to the house layout, I have no choice in the matter).  However, in my system, inserting an unscreened RJ45 connector between two STP cables connecting the switch to the NAS does bring a sound improvement: Slightly better bass control and less splash in the treble.

I've checked this by removing and replacing it: The difference isn't large, but neither is it just on the limit of perception.

I've already tried this Huge, I was not 100% convinced about SQ changes but theoretically it is the right thing to do.  

I also used it to improve (remove) the Cat7 bend into the NAS.  I've found a 90 degree RJ45 UTP M-F adaptor that will have the Cat7 coming in from the side. 

Hi Mike, Yes I believe that any sound differences are most likely related to the local electrical environment and hence variable.

Nice idea with the 90° adapter - I didn't know they existed.  I don't actually need one as in my case the bend is about 3x the minimum allowed radius, so not a problem.  However posting that info may help others.

Here it be .....  Lindy.co.uk have them

There is an "UP" (in photo) & "DOWN" versions available 

RJ-45 male to RJ-45 Female
CAT5e/6 compatible
10/100/1000 Base-T
10 year warranty

Re:  UTP angled connector (photo prev post)  Apart from a super tidy up of my NAS Ethernet entry, I use this UTP connector to break the unwanted 2nd ground on my network.

It’s advised to only have one STP shield ground point. I have this at my NDX via its protective earth,  but recently discovered I had a 2nd ground at the NAS connected to protective earth via its 12vDC SMPS.

I measured the PD between each ground flowing in the shield & found variable low levels of mV. I’m not convinced this level is a problem,  but it must be better with zero so if nothing else it’s now correct.

As for SQ changes – its not huge, but to my ears it is smoother & has more definition with voice/instrument texture & tone & with a hint of better stereo focus. 

My takeaway on this? its worth checking you only have one ground point on your STP cables.  If the network switch/router has unshielded ports nothing to worry about.  But if you have an all STP network with shielded ports on the switch/router & more especially if the various components on the network are powered from different mains circuits, its worth investigating. Its not hard to correct with any type of UTP (shield dis-connector) and/or a section of UTP cable.

+1, I found exactly the same!

One further comment...

With analogue connections, introducing another socket/plug pair would degrade the signal quality.  With Ethernet, it's a different matter unless the new connection causes network errors, the audio data received by the streamer are unaltered, from that perspective the sound will be unchanged.

The changes that may occur are in the interference signals that also get into the streamer, and this can actually be beneficial as Mike has shown.

I just ordered a Sarum TA Interconnect to replace a Hi-Line and having read this post, I ordered a couple of C-Stream Ethernet cables to compare to my Cinnamon's.  If they are better, I'll replace the third one with another C-Stream or (heaven forbid) an Indigo. 

The problem with the Indigo is that even my pal MM wouldn't buy it if I tried to sell it

Bud

I can only assume that the name Indigo arises from what you are supposed to say to the cable when you install it. 

I'll be curious as to what you discover as I currently run all Cinnamons. I did recently swap out one length of Cinnamon for a standard Cat 7 and while it seems to lessen some of the harshness (less revealing?), it was just too polite and took away a lot of the fun and bounce of the system. Reminded me more of my old 5i and CD 5i - elegant but just a bit plodding. This is subtle stuff, and like a lot of hifi I'm sure there's no right and wrong, and many may not even notice. Went with the Cinnamon as I got most of it on sale, and it's very good value here in the US. Alas Chord is quite pricey in the US, though much cheaper in the UK as the pound comes down, but Chord won't allow it sold outside of their dealer system (so no UK to US sales). 

I find no harshness with the Cinnamon cables.  I'm running them through a switch.  NAS to switch, UServe to switch and switch to NDX.  The NDX feeds a SN2 via a Hi-Line (to be replaced with a Sarum TA).

Speakers are Harbeth 30.1's and headphones are Sennheiser HD-800's connected to a Headline/HCDR combo with a Cardas Clear headphone cable.

I'm sending the Headline and Hi-Line to Chris West to be converted to a DIN input.  The Hi-Line also has to be modified.  I won't get them done until late next month.  Chris is also going to put a DIN plug on the captive cable he's removing so I can sell the Headline w/o having to sell the Hi-Line.

As for reviewing the C-Streams vs the Cinnamons, it will take a while to make sure the C-Streams are settled in.

I should add that I make sure all the devices w/switching power supplies are kept well away from those with linear supplies and plugged into a separate circuit. 

Bud

You'll need to check that you only have one earth point on the Ethernet screens - this should be at the NDX.

Dare I point you towards the discussions on problems with multiple grounds on Ethernet networks.

Your Cinnamons  & C-streams are all Cat7 & will carry a ground thru the whole network & I know you have  ground on the NDX & expect also on other devices.  

After I finished my own ground rework,   I found subtle improvements at first in all areas, but after longer listening over a weekend I have proven to myself that it's not so subtle & 1 ground is very worthwhile.

PS damn  that Huge beat me a'gin 

Is it a problem with devices powered by switching devices?  If so, what should I do about it? 

Bud

I doubt Chord has ever heard of In Ya Go.

Bud

It can be a problem with SMPS or linears.  For instance the ND5 XS has a linear supply and is earthed, my Synology Diskstation has a SMPS and is also earthed.

The best way to find out is by unplugging all but one screened Ethernet cable from the device you want to test, pulling out its power plug then checking continuity from the Ethernet screen to the earth pin on the plug.

To fix it (if you do have multiple earths) is to decide which of the extra earth point(s) you want to disconnect, then replace the single screened Ethernet cable(s) to that device with two shorter ones connected by an unscreened 'straight through' RJ45 coupler.  This leaves the signal cables connected but doesn't connect the screens - problem solved.

If you use multiple mains power connections then the difference can be quite large.

For some diagrams on this see Appendix A in:

https://drive.google.com/file/...NVk/edit?usp=sharing

Thanks for the link.  I'll look it over and do so testing as you suggest.

Bud

I have all my linear devices sitting on a Fraim plugged into a power strip which is plugged into one outlet.

The switching devices are in an equipment cabinet plugged into a power strip which is plugged into an outlet on a different circuit breaker.  I once plugged both into the circuit with a common CB and it didn't sound very good.

The way it is now, it's dead quiet and no sign of a problem.

Bud