GROUNDING

[barrows]

OMG, I just came across another review of a very expensive "Audiophile Grounding Box", and there was so much mis-information and outright lies (in an interview with the designer!) that it just about made my blood boil.

A quick few words on "grounding":

 

1.  If any audiophile is concerned about grounding, the very best thing one can do is use true balanced/differential components.  There is no reason to use single ended (RCA) components in a high end audio system anymore, as there are numerous choices one can purchase to avoid single ended circuitry.  And please, do not give me that old trope about how most components are not truly balanced internally even though they have XLR connectors, this is just not true in so many cases as to be silly.  Some components which offer true balanced circuitry:  Hypex, Purifi, Benchmark, PS Audio, Bricasti Design, Ayre, Aesthetix, Chord, Constellation, etc, etc, etc.  The list is long!  Additionally, contemporary DAC chips and phono cartridges both have balanced outputs standard.  With balanced signaling there is no audio circuit reference to 0 volts (or ground if you prefer)-in other words, the signals do not care what is on ground at all.  Balanced signals only reference the voltage difference between the two lines, neither of which is at ground.  So there's no ground "issue" with properly implemented balanced signaling.

 

2.  If you still insist on using RCA connected gears, stop reading now, you are on your own, and please feel free to purchase as many overly priced audiophile grounding accessories as you might choose to.  But your money would be better spent on balanced components in the first place.

 

3.  Use properly designed XLR cabling: a proper XLR cable has signal conductors for the pin 2 and 3 connections, surrounded by a shield which is connected at both ends to pin 1.  Nothing else should be connected to pin 1.  Some audiophile cable companies do not do this correctly, so check.  There should not be any wire connected to pin 1, pin 1 is shield.  Inside your components the XLR shell, and pin 1 should be connected directly to the chassis, this creates a continuous shield of the chassis-cable shield-and the subsequent chassis.

 

4.  If one pays attention to the above things, there is likely to be no "grounding issue" in the system.  But what about internally, and noise on ground planes, perhaps, especially in mixed signal components (specifically, DACs).  This depends highly on the skill of the DAC designer, and how they handle their signal routing, PCB design, etc.  Suffice it to say, that in a well designed DAC, done by a competent mixed signal designer, implemented in a balanced system context, there will be no issues.  Although some audiophile DACs appear to be designed by analog based engineers who may not have the requisite high speed signaling experience to implement proper PCB layout and grounding to avoid problems.  If your DAC responds to grounding tweaks, be very suspicious of the skills of its design.  Perhaps, in that case, take a look at the low level noise floor of the DAC in published measurements and see if it shows problems, and if it does, consider replacement with a better implementation by a competent mixed signal designer.

 

5.  If you play vinyl, insist on a phono stage (and turntable wiring) which can take advantage of the balanced output of phono cartridges.  It is absurd that phono stages are not always balanced, as with their high gain they likely have more to gain from balanced connection than any other component.

 

And finally, if you still insist that audiophile grounding boxes make a difference in your system, go back and figure out where the problem is instead of applying a very expensive "audiophile bandaid".

[pas]

3.  Use properly designed XLR cabling: a proper XLR cable has signal conductors for the pin 2 and 3 connections, surrounded by a shield which is connected at both ends to pin 1.  Nothing else should be connected to pin 1.  Some audiophile cable companies do not do this correctly, so check.  There should not be any wire connected to pin 1, pin 1 is shield.  Inside your components the XLR shell, and pin 1 should be connected directly to the chassis, this creates a continuous shield of the chassis-cable shield-and the subsequent chassis.

 

Hello Barrows - is the following diagram accurate to your statement above? Thanks in advance.

 

http://www.gothamaudiousa.com/productdata/11001.pdf

[ASRMichael]

I use Black Ravioli grounding boxes, connected to HDMI, RCA’s. With great results. 
 

My DAC has XLR connectors, I use the RCA’s, why? Because my Amp is an unbalanced design. My amp with accept XLR, according to the designer if I use XLR is needs to converted back. 

[barrows]

8 minutes ago, pas said:

3.  Use properly designed XLR cabling: a proper XLR cable has signal conductors for the pin 2 and 3 connections, surrounded by a shield which is connected at both ends to pin 1.  Nothing else should be connected to pin 1.  Some audiophile cable companies do not do this correctly, so check.  There should not be any wire connected to pin 1, pin 1 is shield.  Inside your components the XLR shell, and pin 1 should be connected directly to the chassis, this creates a continuous shield of the chassis-cable shield-and the subsequent chassis.

 

Hello Barrows - is the following diagram accurate to your statement above? Thanks in advance.

 

http://www.gothamaudiousa.com/productdata/11001.pdf

Yes, pro audio companies generally do this correctly, as their cables need to work noise free in long runs and in complex studio environments.  This cable is also star quad, which allows for further noise reduction.  Note though, that some star quad cables (not all) are higher in capacitance, and may reduce high frequency response because of that.

[barrows]

9 minutes ago, ASRMichael said:

I use Black Ravioli grounding boxes, connected to HDMI, RCA’s. With great results. 
 

My DAC has XLR connectors, I use the RCA’s, why? Because my Amp is an unbalanced design. My amp with accept XLR, according to the designer if I use XLR is needs to converted back. 

As mentioned, if you use single ended connections, you can ignore the rest of my comments.

[pas]

1 hour ago, barrows said:

Yes, pro audio companies generally do this correctly, as their cables need to work noise free in long runs and in complex studio environments.  This cable is also star quad, which allows for further noise reduction.  Note though, that some star quad cables (not all) are higher in capacitance, and may reduce high frequency response because of that.

Thanks! Greatly appreciated.

[sandyk]

2 hours ago, barrows said:

As mentioned, if you use single ended connections, you can ignore the rest of my comments.

 

 It would appear that more BS about artificial Earths (A.K.A. as ANTENNAS)  has got you all fired up and into pragmatic mode.😜

Not everybody is plagued by the earthing problems that so many in the USA especially, appear to be affected by , in part due to the much lower AC voltage supply at double the current. 

 Well designed unbalanced components using modest length interconnects of typically !M or so  length can have just as good an Audible performance at lower overall cost and reliability than with the added electronics and closer matching of them needed ,even if there is a measured couple of dB in favour of Balanced around  -130dB or thereabouts .

 

 However, IF you need to have widely separated components, then balanced technology is obviously the way to go.

[R1200CL]

https://translate.google.com/translate?hl=en&sl=no&tl=en&u=https%3A%2F%2Fsenorc.no%2F%3Fp%3D226&sandbox=1
 

https://senorc.no/?p=226
 

[ASRMichael]

2 hours ago, barrows said:

As mentioned, if you use single ended connections, you can ignore the rest of my comments.

Now I know what single ended means. 👍

[jiminlogansquare]

@barrows, where do USB cables fit into all this? I have one with an attached “grounding cable” the utility of which I never understood.

[barrows]

1 hour ago, jiminlogansquare said:

@barrows, where do USB cables fit into all this? I have one with an attached “grounding cable” the utility of which I never understood.

The answer is, it depends.  Most good USB inputs on DACs these days are isolated, so the ground has no influence on the DAC circuitry, in which case I would not concern myself at all with the USB cable ground.  If the DAC does not isolate the USB ground, then you hope that the DAC designer knew what they were doing, in which case there is no cause for concern either.  If the DAC designer did not know what they were doing, get another DAC.  If messing with the  USB ground changes things for the better, get another DAC, as this is an indication that the designer did not know what they were doing, and there are likely other things in there which are compromised as well.

[jiminlogansquare]

Thanks; this is helpful and reassuring. I find no audible difference whether the USB ground cable is connected or not with my T+A DAC 8 DSD. Same story previously with my last DAC, a Schiit Yggdrasil. And while you don't discuss what might be connected at the other end of the USB cable, for the record and a sense of completeness,  the other end is connected to an opticalRendu, which also is not being audibly affected by the use or non-use of the USB grounding cable.

[Blackmorec]

On my Synergistic Research cables, the earth leads are connected to the screen. In my system it’s one of many things that when taken together contribute to a holographic soundstage based on the venue or sound engineering on the recording 

[barrows]

17 hours ago, ASRMichael said:

Now I know what single ended means. 👍

???

[barrows]

18 hours ago, R1200CL said:

https://translate.google.com/translate?hl=en&sl=no&tl=en&u=https%3A%2F%2Fsenorc.no%2F%3Fp%3D226&sandbox=1
 

https://senorc.no/?p=226
 

Not sure why the above is here?  Ground loops of some amount are unavoidable, yes, they can be reduced somewhat by careful addressing of the issues, but especially loop currents at high frequencies are always going to be present to some degree.  This is just another reason to choose balanced circuitry which does not care about a ground loop.

The point I am trying to make in this topic, is that adding extra wires to one's components, going to some kind of box which claims to solve grounding issues, is not the way to solve system problems or improve system performance.  In many case this approach will just make things worse, as adding extra wires is also adding antennas which can be a source of additional noise.

 

The above from Mr. Stein also contains some bad information, such where he suggests that single ended connections contain only one signal wire.  This is not true, there can never be any signal on a single wire, as there is no voltage difference on a single wire, or current return path.  But, if one does choose to use single ended connections, then more attention must be paid to grounding issues, as the signal wiring is influenced by ground, unlike with true balanced signaling.

 

There is some good reading here on the subject:

 

https://www.hypex.nl/img/upload/doc/an_wp/WP_The_G_word.pdf

 

[ASRMichael]

1 hour ago, barrows said:

???

As I said, I now know what single ended means. I didn’t know the term until you said it. Excuse my ignorance. 

[barrows]

Just now, ASRMichael said:

As I said, I now know what single ended means. I didn’t know the term until you said it. Excuse my ignorance. 

No worries, have you tried running the XLR connections in your set up ever?  I am not sure how the inout stage in the ASR is configured, it may take advantage of balanced input, eventhough it converts it to single ended at some point: if so using a balanced connection woudl still be an advantage.

If it converts balanced to single ended through a summing circuit, the balanced connection would have an advantage, if it just uses half of the balanced signal, then there woudl probably be no advantage.

[lucretius]

On 12/30/2020 at 1:12 PM, barrows said:

Some components which offer true balanced circuitry:  Hypex, Purifi, Benchmark, PS Audio, Bricasti Design, Ayre, Aesthetix, Chord, Constellation, etc, etc, etc.  The list is long!

 

Thanks for the list.  Hypex and Purify are DIY and the others, except for Benchmark, are somewhat pricey.  I was wondering if you could mention others, especially "affordable" components.  Thanks in advance. 

[ericuco]

19 minutes ago, lucretius said:

 

Thanks for the list.  Hypex and Purify are DIY and the others, except for Benchmark, are somewhat pricey.  I was wondering if you could mention others, especially "affordable" components.  Thanks in advance. 

 

There are several companies selling full assembled Hypex and Purifi amps:

 

Nord, Apollon, VTV to name a few.

[sandyk]

3 hours ago, barrows said:

If it converts balanced to single ended through a summing circuit, the balanced connection would have an advantage

Additional ACTIVE circuitry is rarely a good idea. It is rarely better to use op amps in tandem from the audible viewpoint.

This article from Douglas Self may be worth  a look for an explanation about  Balanced technology. Fig. 9a applies here.

http://www.douglas-self.com/ampins/balanced/balanced.htm

[barrows]

27 minutes ago, lucretius said:

 

Thanks for the list.  Hypex and Purify are DIY and the others, except for Benchmark, are somewhat pricey.  I was wondering if you could mention others, especially "affordable" components.  Thanks in advance. 

I do not really know what "affordable" means, as it is relative.  But, there are plenty of Hypex and Purifi based amps at prices that I consider extremely reasonable for the quality of sound they provide, like Nord, Apollon, VTV, etc.  PS Audio makes balanced products in their "stellar" series which are not all that spends.  Benchmark makes balanced amps and DACs which are not that severely priced, and I am sure there are many others.  My list was just meant to show some examples and not meant to be exhaustive by any means.

[ASRMichael]

5 hours ago, barrows said:

No worries, have you tried running the XLR connections in your set up ever?  I am not sure how the inout stage in the ASR is configured, it may take advantage of balanced input, eventhough it converts it to single ended at some point: if so using a balanced connection woudl still be an advantage.

If it converts balanced to single ended through a summing circuit, the balanced connection would have an advantage, if it just uses half of the balanced signal, then there woudl probably be no advantage.

Yes tried XLR but doesn’t sound as good, that’s not because of the XLR. It’s because the RCA has direct connection bypasses the input relays or something like that. 

[R1200CL]

On 12/30/2020 at 7:12 PM, barrows said:

And finally, if you still insist that audiophile grounding boxes make a difference in your system, go back and figure out where the problem is instead of applying a very expensive "audiophile bandaid".

I wouldn’t mind if you could go into Nordost’s boxes, and do some explanations. I personally think they only do a ground lift and ensure to equalize possible possible variations in potentials.

 

[barrows]

As most companies making these type of products do not really disclose what they are doing, it is hard to evaluate them from any technical perspective.  Most components are already grounded by their AC cables, and good AC cables include a nice stout (high gauge) ground wire with very low impedance to wherever they are plugged in.  It makes little sense to attach an additional "ground" to a component as this then makes for two grounds, or even three!

Best practice for grounding a system would be to use a single power distributor or conditioner, which all the components plug into, using quality power cables with stout ground wires in them.  Then do not attach additional ground conductors.  It nearly always going to be better to have the system wiring be as simple as possible.

If one is concerned about keeping the components at the same ground potential, one should rely on the power cable connection for this, not some additional wiring, and have all the power cables connect to the same distribution point.

 

I keep my system simple, everything (except sub) is plugged into a single Cardas Nautilus power distributor.  The Nautilus does have heavy gauge inductors on the ground wiring only, which serve to reduce any very high frequency currents circulating on the ground, but the inductors do not hinder current flow at all anywhere near the audio range.  The sub is plugged into the same wall outlet (Cardas) as the Nautilus power strip.  All my (DIY) power cables have stout, 11.5 or 10 AWG ground wires to insure low impedance.  The sub is the only component connected by RCA cables, and it has the capability to lift its ground connection to the wall if necessary (I leave it grounded, as I tested both ways and there are no issues).  The Ethernet audio feed coms to the system over optical cable, so it avoids electrical connection to the other computer gears (elsewhere in the home).

[barrows]

2 hours ago, R1200CL said:

I wouldn’t mind if you could go into Nordost’s boxes, and do some explanations. I personally think they only do a ground lift and ensure to equalize possible possible variations in potentials.

 

I would say, in regards to Nordost's grounding box, on their website description, they do suggest it is applicable for those systems which do not already have a good ground.  At least they are being honest about their grounding unit's purpose.  One could conclude from what they say, that a system which already has a sound AC ground point will not benefit from their grounding unit.