Noisy Mains, and how to tackle it

Check out Russ Andrews for various solutions. Some bulky, mostly not silver coloured, although silver used in some of the more eye-wateringly expensive mains cables!

 Have you changed your Rack ? Make sure rack is setup correctly.

Check the fuse on the spur give it a clean,  try a different fuse or turn the one you have around the other way.

Try a different wall plug.

Cable dressing may help.

Make sure you leave your system on all the time.

Loki posted:

Check out Russ Andrews for various solutions. Some bulky, mostly not silver coloured, although silver used in some of the more eye-wateringly expensive mains cables!

One has to be careful to avoid the "snake oil" element in what these manufacturers claim to justify their high prices - in this case $6k+ I think for the product mentioned in the original post? I use a Russ Andrews XBlock which is powered from 1 side of a double wall socket into which my TV, Router, PS4 and LP12 is connected. RA use passive filtering for clarity. I have a CHC Hydra for my Naim kit from Sean's Silver Range plugged into the other other socket. Both are enabling silent running and the TV picture is noticeably better as an added benefit. Sean will also alter cable lengths as each one is built to order. 

Fortunately, both manufacturers offer 30 day sale-or-return terms so if you're not convinced you can get your money back. Isotek are another well-respected company and I've used their plug-in mains conditioners in the past to create "dead spots" around fridges and other white goods. RA do these too so maybe worth trying one of these out and for £75 or so, it's very low risk.

If you can’t accommodate a big ugly box in your living room, can you hard wire a similar device into your dedicated mains circuit and put it somewhere more discrete? I believe some forum members have done this successfully with a box hidden in the garage  

Loki posted:

Check out Russ Andrews for various solutions. Some bulky, mostly not silver coloured, although silver used in some of the more eye-wateringly expensive mains cables!

Good advice. Just be aware that what some manufacturers rate as 'better' can just mean 'different'.

It's why Naim do not promote/endorse mains conditioning devices. They do something for sure. It's just a matter of whether the individual likes that something or not. With a poor quality mains supply; such devices can help.

I have a dedicated spur and still get tranny-buzz on occasions. I can't say that it has any impact on the SQ though. There used to be a  4pm ish dip when all the 'just out of school' computers were fired-up. But I suppose most of the young folk are on SmartPhones these days and charging them through the night.

John.

Get an electrician in to to a test on the mains supply. If possible get a dedicated supply for the system on its own consumer unit.

I think Naim are wary of  some mains filters, as they can effectively add impedance to the mains supply for the filtered device, or can couple Hf in the live and neutral to the earth and this can affect performance... however there can be some very good mains filters, but necessarily the better ones that address lower frequency noise that have minimal/no impact on performance will be bulky.. kind of laws of physics. Russ Andrews offer some parallel filter devices that cater for the higher frequencies only and are benign to impedance issues therefore seem to work well with Naim and these can be quite effective ... but their affect reduces over time and need regular servicing with RA so as to maintain top performance.

The other thing that might be happening is that your earth ground has HF/RF noise on it compared to neutral or live... this can be an issue with PME/TN-C-S  supplies. The solution here is to get an electrician to convert, where possible, your supply to a TT supply, this is where you have your own local earth ground electrode, and is carefully but crucially disconnected  from your noisy mains supplier earth. This did the trick for me and gave me great benefit.

Please note however... NEVER try and DIY and put your own ground electrode on a PME supply, this can be extremely dangerous leading to potentially lethal or intense heat/combustible/explosive  conditions in case of certain supply distribution faults.... always used a qualified electrician... but also bear in mind a TT earth system might not be possible in more concentrated housing such as flats and apartments.

A balanced (isolating) transformer installed on the circuit fixes a multitude of mains issues. As they are bulky, it can be best to route the curcuit through a garage or something to house the item.

There are hifi grade ones out there made in both the UK and US which cost a fair bit. But much lower cost medical grade ones should work well also (NMRI and CAT scanners are sensitive to mains noise so isolating transformers are mandatory on many hospital circuits).

Important to note, they are not filters. Simply 1:1 ratio windings to give identical output voltage as the input voltage for their rated current limit. They simply decouple your circuit from the mains. 

FZ, isolating transformers are ideal at removing DC offset.. and some have additional RF/HF filtering built in. However if the issue is noisy safety earth I am not sure they will help with that... unless they allow you to separate safety ground to a local electrode .. but if so again these sound like a qualified electrician would need to fit or be council assessed and certified if you do it yourself (To be legal in the UK)

Simon-in-Suffolk posted:

FZ, isolating transformers are ideal at removing DC offset.. and some have additional RF/HF filtering built in. However if the issue is noisy safety earth I am not sure they will help with that... unless they allow you to separate safety ground to a local electrode .. but if so again these sound like a qualified electrician would need to fit or be council assessed and certified if you do it yourself (To be legal in the UK)

Absolutely and I wouldn't suggest otherwise. I've never seen one that had anything but an earth passthrough.

And yes, they really should be purchased in the country of use for regulatory compliance. As simple as these devices are, one of matching voltage may be unusable for compliance reasons. I remember looking them up where I live to find that toroidal models are not certified and above a certain size must be fitted atop a 40 foot concrete utility pole. Most countries provide fewer restrictions.  Yet they are common enough for so many industrial applications, bring up the topic with your sparky should see you right. 

FWIW dedicated audiophile ones go for about 10x what regular medical grade ones of similar current handling go for. The main design difference as far as I can see is audiophile ones are toroidals wrapped in Faraday mesh versus industrial block transformers. I suspect in a domestic setting, the cheaper industrial ones work just as well.

Loki posted:

Check out Russ Andrews for various solutions. Some bulky, mostly not silver coloured, although silver used in some of the more eye-wateringly expensive mains cables!

Thanks, I forgot about RA and his products and will look into them.

I use a balanced mains transformer.  I find it a step in the right direction, without using mains filtering

Sounsfaber posted:

 Have you changed your Rack ? Make sure rack is setup correctly.

Check the fuse on the spur give it a clean,  try a different fuse or turn the one you have around the other way.

Try a different wall plug.

Cable dressing may help.

Make sure you leave your system on all the time.

 

Thanks to you as well. Regarding your suggestions:

Yes, the new one slightly improved things.

Got a new fuse together with the spur.

Tried that too, no discernible difference.

Power and signal cables are separated as far as possible.

 It is.

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I’ll try to borrow one of these and see what happens.

Simon-in-Suffolk posted:

I think Naim are wary of  some mains filters, as they can effectively add impedance to the mains supply for the filtered device, or can couple Hf in the live and neutral to the earth and this can affect performance... however there can be some very good mains filters, but necessarily the better ones that address lower frequency noise that have minimal/no impact on performance will be bulky.. kind of laws of physics. Russ Andrews offer some parallel filter devices that cater for the higher frequencies only and are benign to impedance issues therefore seem to work well with Naim and these can be quite effective ... but their affect reduces over time and need regular servicing with RA so as to maintain top performance.

The other thing that might be happening is that your earth ground has HF/RF noise on it compared to neutral or live... this can be an issue with PME/TN-C-S  supplies. The solution here is to get an electrician to convert, where possible, your supply to a TT supply, this is where you have your own local earth ground electrode, and is carefully but crucially disconnected  from your noisy mains supplier earth. This did the trick for me and gave me great benefit.

Please note however... NEVER try and DIY and put your own ground electrode on a PME supply, this can be extremely dangerous leading to potentially lethal or intense heat/combustible/explosive  conditions in case of certain supply distribution faults.... always used a qualified electrician... but also bear in mind a TT earth system might not be possible in more concentrated housing such as flats and apartments.

Hi Simon,

thanks for your input. I had a shunt-to-ground type for a short time and it made things considerably worse, both with my previous electronics and the current ones from Naim. 

As I have no idea if a separate ground is legal here in Germany, I might try one of the ground and/or earth conditioners, like the Computer Audio Design Ground Control. From what I have read about it, no laws of physics have been altered during its design and it’s relatively small and black 

Mulberry posted:

 

, I might try one of the ground and/or earth conditioners, like the Computer Audio Design Ground Control. From what I have read about it, no laws of physics have been altered during its design and it’s relatively small and black 

This device looks interesting. How would you connect it up to your system ? As there's a few options. Does your music line powerigel plus have an earth post ?

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The easiest way and the one I'd likely try first is to connect it to the ground post on either the SN2 or the phono stage.

The Powerigel wouldn't allow a direct connection. The safe way would be via a multi-way outlet, wit hthe Igel into one outlet and the Ground control parralel to that. If this turns out to be the way forward, I may have to move on from the Igel.

I am interested in an mains isolation transformer ...can any point me in the right direction for a recommended on ??

For compliance reasons you need to choose one authorised for domestic use in your country. Can you indicate where in the world you are?

But as they need to be installed by an electrician, you might start there. In the US and Japan almost all buildings use them for double voltage circuits for air conditioning. Any electrician with half a clue can discuss these with you.

Japtimscarlet posted:

I am interested in an mains isolation transformer ...can any point me in the right direction for a recommended on ??

If you're in the UK then google Airlink Transformers. 

Worth doing a search on balanced mains on the forum. There are a few threads with some good advice and recommendations. 

Was scratching my brain trying to remember. Equitech (US) are supposedly the gold standard for audio grade isolation transformers. They list which voltages and countries they are certified for. But very expensive.

Again, a sparky can put you onto more common solutions... and possibly investigate your earthing issues too.

what tests/checks can one perform to confirm a 'noisy' earth -- other than poor hifi sound, which can also be for umpteen other reasons?

ken c posted:

what tests/checks can one perform to confirm a 'noisy' earth -- other than poor hifi sound, which can also be for umpteen other reasons?

 

There are a few gadgets that are easy and safe to use..

Blue horizon do one

feeling_zen posted:

For compliance reasons you need to choose one authorised for domestic use in your country. Can you indicate where in the world you are?

But as they need to be installed by an electrician, you might start there. In the US and Japan almost all buildings use them for double voltage circuits for air conditioning. Any electrician with half a clue can discuss these with you.

I'm in the UK 

I'll look at the airlink ones and see what they are offering...

TOBYJUG posted:

ken c posted:

what tests/checks can one perform to confirm a 'noisy' earth -- other than poor hifi sound, which can also be for umpteen other reasons?

 

There are a few gadgets that are easy and safe to use..

Blue horizon do one

tobyjug, many thanks :-)

enjoy/ken