I see many adverts for mains interference suppression blocks for 4 or 6 sockets and once again I am in need of such a unit due to the dreaded fridge or LED lighting issues.
Does anyone have suggestions of makes that have really worked well since as the title says it might be an expensive lottery.
None of the equipment manufactures use such devices in the way of keeping consistency for average everyday installations.
These have always been frowned upon by true audiophiles as taking something out.
Naim thankfully still seem to bear this out.
No nonsense blocks and quality Powerlines.
But these days the ten minute experts usually from the fake sound earbud and AV generation have different ideas.
I say use the gear as intended or spend your money chasing fads and flavours. 
IMHO
Stop sitting on the fence 
Opinions vary, as with anything hi-fi. The Puritan PSM156 block has some strong supporters, and not at too a silly price. Perhaps get one on sale or return? Only your ears can decide if it works for you. There are of course many far more expensive solutions from Shunyata etc.
The other tack to consider is a Balanced Power Supply such as Airlink make. Either that or get rid of the offending kit!
Not aure about the title but I guess the idea is to avoid the power suppression!
Anyway, after trying many good ones, I now have 2 of these at home, one for each setup:
The SOtM MT-1000.
My mains is very noisy (remote rural area) and with added DC offset my transformers can hum quite loudly.
I have only briefly heard my system with a DC blocker (hum stopped) and also a mains filtered 6-socket but need to listen properly and critically before I reach any conclusion.
When I tried filtered mains over 20 years ago, to my ears it sucked the life out of the sound of my system.
I thought it worthwhile trying again with modern equipment to hear if it still does and plan to do so soon, preferably without seeing which configuration my dealer has plugged in. A blind test.
Precisely, itâs essentially an ideology, weâve been conditioned (no pun intended) to believe theyâre bad, bound to âsuck the life out of the musicâ as soon as theyâre plugged in, a textbook case of a self fulfilling prophecy.
Sorry they are bad, suck the life out of the music according to my ears, no conspiracy needed.
If they are good they would have been widely adapted by audio companies and audiophiles as standard equipment.
As a matter of fact, they are widely used by high end manufacturers, just go to any major audio show and try to count the rooms without any power conditioning in place.
I think my two Isotek V5 Polarisâ do a very good job of filtering out noise on my mains as both my main and second HiFi Systems are sounding excellent.
My house has a 6kW AirCon Unit, a large 7kW Solar Panel System, 2 pumps for the swimming pool, a very large wine fridge and two large fridge/freezers, a washing machine, tumble dryer and 4 mains transfomers for 12 volt LED light strings, so lots of electrically noisy equipment, but neither HiFi System is affected by this noisy equipment, so Im pretty sure the Isoteks are doing a very good job in filtering out the noise on the mains.
I would recommend Isotekâs, they have a few different models to choose from.
People mention ânoisyâ equipment. What is meant by these. In the UK at least there standards and regulations that limit device emissions and also its tolerence to small variations on the mains.
So what is being referred to? Power factor noise, transient noise, high frequency noise? All of these things require different or very different treatments.
I suggest if you are experiencing the effects of noise on equipment, something somewhere might be broken and out of spec and worth hunting it down and removing it. It may also be a symptom of faulty wiring.
Bad perturbations on mains can cause faults with computers, lessen the performance on TVs as well as include clocks and pops on hifi.
I live in a rural location, my mains is quiet in some regards, but noisy in others such as regulation⌠and that may well look different to the mains on a housing estate.
That being said as I have written before, one of the largest sources of high frequency and spurious transient noise depends on your earthing setup.
PME systems, which most modern UK houses have and can be inherently noisy. No conditioners can prevent this one reason being is that the safety earth is the source of the noise along with neutral. One of the only resolutions is to have your earthing system converted to a TT system. This will decouple your Earth from the combined neutral and be instead referenced to your house location.
Many recording studios use TT systems for low electrical noise reasons so I am told.
My TT setup was put in for non hifi reasons, but the improvement for my audio gear was a welcome suprise.
Start capacitors on electric motors can cause noise on your mains electricity, run capacitors not so much but still possible.
Transformers can have harmonic distortion that can also effect the mains electricity.
It is appreciated that equipment is designed to specifications and built to tolerances but they can be electrically noisy, which is probably no problem for other/most domestic electrical equipment but sensitive equipment like HiFi Equipment could be effected, as I understand it.
In a domestic setting yes any reactive load starting or stopping can cause a small transient⌠unless the load is not compatible with the wiring, whete it can be larger.
Equipment to be compliant to UK regulations must also be sufficiently tolerant of such affects, such that it carries on functioning as intended.
That being said no conditioner unless itâs a regenerator will prevent most of this,(and regenerators often struggle to provide the very low impedance required for many hifi amplifiers) as they are relatively low frequency.. these are clicks you would otherwise hear, or in the days of filament bulbs you would see them flicker briefly.. say when a powerful vacuum cleaner or a powerful electric drill is turned on.
Usually the best remedy is to have the highly reactive loads on a seperate circuit(ring main or radial) to everything else and have large gauge wiring to keep the impedance low.
Highly reactive loads also have circuitry included to flatten the reactive element (capacitors or inductors). These are sometimes called âfiltersâ or âsuppressorsâ and if they go faulty such as open or closed circuit⌠the reactive surge will reflect around your local distribution.
There are a number of mains blocks on the market that claim to suppress various types of mains interference. I have no idea how effective they will be in suppressing the type of interference you are talking about. All of them however are likely to impact negatively on the music, esepcially in a Naim system, and their use is not recommended. Definitely best avoided. Ideally install a dedicated mains supply for your hi-fi. It wonât reduce interference on the incoming mains but your own particular issue is generated inside your home not externally, so that would be the best option for you by far.
To be clear some products will affect and others wonât Naim equipment.. it depends what it is doing. As I say many quality amplifiers such as Naim require a low mains impedance across the audio band. If that is maintained and is effectively transparent almost certainly it will be benign. If not it will likely affect the performance of the amp.
As I say the best thing for Naim, as it relies on safet earth for the integrity of its unbalanced audio signal, is to have a TT system. This will likely produce the lowest earth impedance to ground. Having seperate wiring alone wonât remedy this⌠but yes in an environment with many large reactive loads will help with clicks and pops breaking through into audio. This can be a seperate ring or radial. A seperate ring over a seperate radial is usually considered beneficial as the impedances remain lower for a given size of cable.
This will not prevent high frequency internal noise from flowing..in most domestic setups⌠here I suggest prevention is key.
You can see for yourself by looking at the mains with on oscilloscope (that can obviously measure higher voltages)⌠and compare your different radials and/or rings⌠say live to Earth.
Turn up the tine base and lock into part of the mains cycle. like across over point. AC couple and turn up the sensitivity.. you can then start to see the noise. Use a CAT II rated probe of course.
If you do, how do you avoid needing/using a mains extension block?
If itâs mostly the fridge, you can try a cheaper filter block on that, you donât necessarily need to try and remove the noise at the hi-fi end, remove it at the source.
Indeed, as it suggests the suppressor on the fridge compressor is faulty or sub optimum
The Chord M6 mains block that I previously used (before returning to a Naim system) was really designed to target HF noise originating from various sources. It was highly effective and there were very obvious beneficial effects in my previous system. When I removed it however I beacame aware of how it seemed to very subtly but noticeably affect timing in a negative way.
Strangely, all the beneficial effects that the Chord M6 brought to my previous system are now all present and correct in my new Naim system, and without any such mains block. Just Powerlines direct to the wall socket. Iâm not quite sure what to conclude from this, because at the time I felt that the M6 was a massive step forwards overall. But in any event, my Naim system gives me all those postive qualities, and without any downside.
