New-school grounding techniques, lunatic fringe or utter necessity?

MikeyFresh

Moderator
Staff member
Site Supporter
On a very basic and simplistic level, I have used 'cheater' plugs to reduce hum in certain configurations. Also works to lift multiple, separate component grounds and tie everything back to the preamp (only works, of course, if the preamp has a three prong AC cord - Never do this if it doesn't).

I may have to explore the devices linked in your post.

Very interesting stuff. :)
 
TubeHiFiNut;n43682 said:
On a very basic and simplistic level, I have used 'cheater' plugs to reduce hum in certain configurations. Also works to lift multiple, separate component grounds and tie everything back to the preamp (only works, of course, if the preamp has a three prong AC cord - Never do this if it doesn't).

I may have to explore the devices linked in your post.

Very interesting stuff. :)

My interest was perked by related issues, the severing of the cable TV ground by use of a Jensen VRD-1FF IsoMax, one too many grounds as you describe above.

In most cases this is used to eliminate a loud hum caused by a ground loop, although I didn't have that problem. I elected to use one of these devices anyway in order to provide isolation from lightning strikes on the cable TV system wires outside the house (in the event their ground were to be compromised in some way), and because many report a better picture and sound quality when using this device. Add me to that group, not a striking difference, but not hard to discern either.

I then did the same sort of thing in between the cable modem and router, using an EMO Systems EN-30 Network Isolator, which clearly elevated the audio performance in my desktop system, a blacker quieter background and larger more focused stereo image.

Now I'm interested in all things grounding.
 
ArcadiaAudio;n43713 said:
Gutwire has a Ground Cable available as well.

Very interesting, somehow doped with white charcoal:
  • Extensive use of natural minerals: Binchō-tan

 
MikeyFresh;n43715 said:
Very interesting, somehow doped with white charcoal:
  • Extensive use of natural minerals: Binchō-tan


Yes, Gutwire uses some very interesting materials in their cables Germanium, Amethyst, Binchō-tan.
 
hey folks.... i have a rega rp6 and it has no separate ground wire and i am getting a bit of 60 cycle hum when volume is at half its not as bad as it was but some days drives me batty ...... any potential solutions would be greatly appreciated
thanks!!!
 
hey Olson Jr thanks so much for sharing this i have a good ground cable i will use and see if the problem is eliminated this is super useful info!!!!!!
 
Hey Now.... i just did as described in the article you so graciously shared! and yea there is an improvement for sure! i have wired my ground to the main screw of the ttpsu and wrapped it around so it contacts the metal not the plastic backer and to my jolida phono preamp big improvement but still hear noise at fullish volume ..... so although it is improved i will at a later date continue to silence the evil humm!! thanks again Olson Jr!!!! Jamhog
 
Recently I've been following the posts on another forum of John Swenson, a design engineer for Sonore, and UpTone Audio (and perhaps others) on the topic of grounding, specific to devices powered by a SMPS.

In short, his research and testing shows that most of these SMPS units are inherently bad not just on a noise level, but also on a less understood and harder to test aspect known as AC leakage current. It was his supposition some time ago after an initial investigation, that AC leakage current from a SMPS is in many cases an equal or greater problem than just the plain switching noise itself. An example of this is the iFi iPower, a $49 wall wart with outstanding low noise specs (1 µV according to iFi), but rather large measured AC leakage current.

It's a somewhat in-depth topic and I won't attempt to fully summarize it here, except to say that previous knowledge and testing in this area (apparently dating back to at least the 1960s and therefore performed on LPS units as SMPS didn't exist yet) was always focused on low impedance pathways for AC leakage current. To this day, there is no off the shelf testing equipment that can easily measure high impedance AC leakage current, so John Swenson built his own custom tester including an ultra high impedance differential probe (around 10 Giga Ohms).

It turns out AC leakage current has not just a low impedance component, but can also exhibit very high impedance components on the order of 300 mega Ohms.

I'll stop there with my attempt at technical explanations, I'm not an EE, and some readers of this post might already be snoozing! Instead I'll mention the John Swenson authored solution which I've found to be transformative in using SMPS units in my 3 audio systems.

It's also worth mentioning at this point that avoiding the use of SMPS units in audio systems wherever possible or practical seems like sage advice, and thats not new or revelatory. An LPS will damn near always sound better, though it is larger, more expensive, and consumes more energy than these new fangled SMPS units do.

The solution John Swenson has prescribed is brilliantly simple and low cost, though it requires a small amount of DIY knowledge and skill. Lacking that, there is also a new off the shelf product that does the same thing as the DIY solution, albeit at $49 per SMPS treated.

John's custom test gear illustrates that ALL of this AC leakage current can be safely and easily shunted to ground with a simple connection to the DC output of the SMPS's negative leg going back to the AC safety ground.

I used a $6.50 Leviton AC plug, a $1.89 ring terminal, and some 14 gauge stranded copper wire at 50 cents per foot.

PA271066.jpg

Finished cable looks like this:

PA271062.jpg

Installed on the output of a Meanwell SMPS (at the input of the powered device):

PA281077.jpg

This produced a rather shocking improvement in low level detail, dynamic contrast, stereo image size, even bass response, etc... all good, and no penalty.

This SMPS grounding technique has tamed detrimental effects caused by the one and only SMPS in my main audio system.
 
Last edited:
OK, color me intrigued.

An SMPS is a Switch-Mode Power Supply... Do all the typical "wall wart" DC supplies fall in this category? I count three of them in my system, and I betcha they're not helping with the noise situation around here! I thought my noise problem was coming from the line (and I know much of it is) but could it be that some of the culprits have been right under my nose, all along?

Hmmm...
 
Do all the typical "wall wart" DC supplies fall in this category?

I believe they do, and in my case even the existence of an IEC 320 inlet on the SMPS brick itself meant nothing, even that side of the supply was not actually grounded (that pin connects to nothing). So this wouldn't even always take the form of a wall wart, the laptop style bricks are similar.
 
Interesting.

I have noticed a few things over the last couple years that may be in-sync with your findings. I have dedicated circuits for audio in my main room and I found getting anything with a SMPS onto the old room circuit - and off the audio circuits - made for improvements in the same areas you mentioned; low-level detail, dynamic contrasts and image size.

With digital devices, I found using a REGEN to isolate DACs - specifically USB powered DACs - from their USB source SMPS was a nice step in the same direction as well. This got even better when I powered those REGENs with a big old inefficient regulated linear power supply.

I've simplified a bit of late but the things that still work and I won't go back from; USB REGENs on both DACs (a MP-D2 tube DAC for playback and Korg DS-DAC-10R for vinyl ripping), LPS power to those REGENs, and keeping all the digital stuff in the room using a SMPS plugged into that separate circuit (playback PC, laptop, LCD monitor, phone charger, etc.).

The other 'digital' tweak I've stuck with is using DIY'ed hard USB connectors between those REGENs and DACs eliminated digital 'cables' there but that would be a lunatic fringe discussion with a different focus. :)
 
keeping all the digital stuff in the room using a SMPS plugged into that separate circuit (playback PC, laptop, LCD monitor, phone charger, etc.).

Is critical.

In this grounding technique the shunt(s) are of course attached only to the AC safety ground of that same separate or "dirty" AC circuit, both to avoid the potential for introducing a ground loop, and to keep the dirty "digital/SMPS" ground fully separate from your audio dedicated AC circuit.
 
Last edited:
The other 'digital' tweak I've stuck with is using DIY'ed hard USB connectors between those REGENs and DACs eliminated digital 'cables' there but that would be a lunatic fringe discussion with a different focus. :)

I would subscribe to that thread :grandpa:.

In that particular lunatic fringe genre I opted out of the DIY route, and got the UpTone USPCB instead.
 
OK, color me intrigued.

An SMPS is a Switch-Mode Power Supply... Do all the typical "wall wart" DC supplies fall in this category? I count three of them in my system, and I betcha they're not helping with the noise situation around here! I thought my noise problem was coming from the line (and I know much of it is) but could it be that some of the culprits have been right under my nose, all along?

Hmmm...
Wow!

I pulled all three of my wall wart power supplies out and plugged them in to a power strip, which is in turn plugged in to one half of a duplex outlet. The rest of the system runs through a large isolation transformer that I use, and in to the other half of that same outlet.

Everything's still on the same circuit but the amps are quarantined from the little SMPS buggers by the isolation transformer.

Things are much quieter!

This is awesome.
 
Back
Top