Grounding at multiple points?

I kind of wonder how late the guy in NYC was able to listen. Did he say? Most of us live in apartments and the neighbors are not going to put up with late night sessions. I don’t listen past 10 pm.

As for power and noise, I just had installed two dedicated audio outlets, 20amp, hospital grade, and on the same phase, along with a new electrical panel.

The engineer who sold me my mighty class A amp, a Gryphon Colosseum, wants me to have a second ground run to the cold water pipe in the kitchen. It’s possible but would require quite a bit of work and expense. The regular ground is through the rigid metal conduit clamped to the panel which runs down six stories to the basement meter and off to ground rods and the water pipe.

The electrician measured from the neutral to the ground in the panel and from the neutral to the cold water pipe in the kitchen and the panel’s ground is better, .2mV vs .4mV, if I recall correctly. I suppose the water pipe has some corrosion along the way.

Still, having two ground paths would be better than having one. Should I do it?

If I want a better listening experience, I need to stop the plane traffic into La Guardia airport, lol.

The new amp moved my sound so dramatically, in a good way, that I am just amazed at what I hear, even though I’m in a noisy environment, being in the city.

Not necessarily. I shifted this to Tinkering where folks who know such stuff hang out.

Single-point grounding also limits the ground loops that occur when more than one conductive path exists between two points. If the electrical equipment is not only bonded to ground bars, as in Figure 1, but to various building steel columns—if available—and if the grounding potential is different in the building due to an electrical storm, on a multi-point grounding system, noise could circulate, cause error in equipment operation and become difficult to isolate.

Source.

Connecting two ground points with different grounding potentials will necessarily create a current between them. Just ground to the best one in my opinion.

An isolation transformer could be worthwhile.

Thanks Andy! Very interesting. Perhaps I will leave well enough alone and concentrate on other improvements.

I know I could Google, but what is an isolation transformer?

You have a massive toroidal transformer that you connect all your audio gear to and it isolates you from the power grid. There are benefits for ground loops as well by having everything plugged into it. Search for Torus or Bryston BIT (same thing - different branding) isolation transformers.

There are other designs out there too, but these ones are massive and don’t mess with dynamics like most power conditioners. In fact they can improve upon it. I use a Torus and have my audio gear plugged into it.

I have also read several articles by engineers/electricians who specialise in audio studio setups who advise single ground is vital.

Thanks, but I probably won’t be able to justify it. Any idea of the rough cost of such a system?

Interesting.

So, ok, one ground, but how do I determine the quality of the ground?

Depends on the system and the power you need. You can get 15A, 20A and higher models. Some have voltage regulation and ethernet control as well as added features. Some don’t have the TOTL surge suppression and you can save further cost. The features regarding noise, isolation, and power delivery are found on all the models. You can sometimes find good used models as well.

Before Torus, I was connecting everything to the same circuit and same outlet/power strip.

This is still what I do in my other rigs where I don’t have a Torus or any other power conditioners. They all work perfectly. Everything on the same circuit and connected on the same Tripplite bar.

I’m afraid I’ve no idea, I’m by no means an expert, just came across the idea a few times when reading/researching mains power (thinking about improvements at my house).

The other thing that became apparent is it’s a pretty specialised subject and even in the pro arena seems like there’s a bit of black art involved. In any event it seems more important than fancy mains wiring (in pro worlds).

@zoom25 the Torus units look great and I’ve heard a few people saying good things but they’re ****** expensive for what they are.

Yes, the Torus are expensive and HEAVY. For some they have solved audible and obvious problems. I didn’t have any problems and just wanted to see if I could make the sound better. The day I got it, I remember being taken back by how dry, cleaner, and slower the music became. Maybe it was expectation bias. I haven’t went back and A/Bed with the power strip (that could be fun).

Subjectively comparing the experience before and after the addition of Torus over months I find the sound to be consistent 24/7. With Class D amps, I can leave the entire system powered on 24/7 as well.

All you need is an isolating transformer with surge protection, ideally on its own circuit.

So you don’t waste lots of money you need to get it direct from a transformer manufacturer and not from an audio manufacturer. You don’t need to have it plugged into the network and monitored. It’s such a simple piece of electrical equipment.

I live in the UK and use these guys, but you should have something similar in your country; https://airlinktransformers.com/category/balanced-power-supply

Ha, 24/7 Class A will bankrupt me. I’m not looking toward to my first electric bill with the new amp. Still, I hope I can afford three or four hours a day of heavenly sound.

I have a low bias option that runs cool but I can hear the difference. A certain palpability disappears when using the low bias option.

Can I ask your experiences and with any specific models. I was really taken with this co for their pricing and non audiophileness, but I couldn’t decide between filtered or unfiltered, and then started reading that balanced can be dangerous. But living in London I’d love to see if the power noise really is a factor. Certainly I feel like music in the evenings and weekends is better at my house, but appreciate this could also be completely down to psychological reasons… I wouldn’t want to buy a Torus to experiment, but an Airlibk would be OK - if safe! (Have a little one to think of now).

Closest to zero. 0.2 mV is better than 0.4mV.

I have no idea what the electrician was measuring against though.

That’s what I figured, closest to zero is better. He was measuring from the neutral leg in the panel to the ground on the panel (.2mV), and the neutral leg in the kitchen and the cold water pipe under the sink (.4mV).

Another option might be the radiator pipe. We didn’t measure that.

A difference isn’t ideal but as long as all your gear uses the same it should have little impact. One ground, even a less than ideal one is better than two grounds at different potential with gear spread across them. This is the classic ground loop.

Sorry for the late reply, didn’t see the notification.

The decisions on the various transformers goes something like this:

Will you be installing a dedicated circuit? If yes, you can get the transformer that is hard wired into the circuit. You simply have to calculate your power requirements and buy the right size. Then from the fuse board a wire goes into one side of the transformer (primary) and out (secondary) to your line of sockets. A radial circuit this will be and you can have as many sockets as you’d like.

If That is impractical you can add it onto your ring main and create a spur and then have you radial sockets coming off the secondary as described above.

These transformers work by removing the earth link, in effect making it an earth free circuit. It gets around the danger of not having earthing by using and rcd. How that works is not something I can explain on my iPad. :grinning:

The separation (or isolation, hence the term isolation transformer) allows our equipment to be at equi (equal) potential. We also do this with analogue interconnects through balanced xlr cables for example.

If you are just going to be plugging a few things in, airlink also makes the transformer with sockets in it. Same principle as above but a simplified plug and play solution.

The other decisions are if you want the supply filtered. The idea is good, but the more you filter the more it impacts the sound. It is a compromise. They are designed for situations where the supply is particularly dirty. It is more prevalent in America and Australia, but in U.K. we are fortunate to have a decent supply. If you lived on an estate next to an industrial estate with lots of high loads and plenty of heavy industrial machinery, then filters can help.

It’s very much the same as TV (and audio) processing. We want DSP turned off as much as possible to get the purest sound/picture but in some cases, like dodgy SD cable broadcasts we have to turn on some processing to improve the overal picture.

Other factors to consider is voltage stepping. Again in US in particular the voltage can fluctuate. So you can have transformers that step-up or step-down the voltage. Again it’s not something that really happens in U.K. Equipment is designed to work in a voltage range and as long as your supply is in that range you’ll be fine. Because of European harmonisation our voltage is 230V.

The one thing you do want it to have is surge protection. This protects your equipment if there is lightning or a power cut and when it gets turned back on there can be some serious surges. If you imagine turning your entire house on at the same time, there is a big load all at once. Well multiply that 1000 times when the supply authority turn their transformers back on for every house and business on the same supply as you and it’s clear to see you don’t want that hitting your sensitive equipment.

So tell me what sort of installation you want I can can help advise on the right transformer for you.

At the end of the day you are trying to create a clean and stable circuit. Stuff that have large inductive loads like household appliances (fridges in particular) will affect your circuit. That is why you want your sound equipment circuit to be separate. Ultimately how you achieve that is up to the individual. For me, I created a new circuit and hardwired in an isolation transformer.

Voltage is the potential difference between 2 conductors. We measure our potential voltage between line (live) and neutral. A potential difference of 110V is what you normally see I assume in US. For U.K. it’s 230V.

Whereas there is a difference between line and neutral, earth and neutral should have equipotential. They are physically connected at the star point of the transformer at the supply authority. What he was measuring was the neutral against the earth or he could have been measuring against various earths in your household to see if there is any leakage from line. This can happen if appliance breakdown or joints, cabling perish over time.

What causes the ground loop hum is using multiple earths, usually using different sockets on different circuits that have a different potential.