Dedicated mains - Survey

Next up: Naim to sell PowerLine cable from the drum for only 600 per meter

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Can you explain what spec these cables fail to meet, and how you arrive at this figure?

Little details make all the difference added up. Thank you, Spanna.

How do you know if the printing on the outer sleeve is always the same way round relative to the drawing direction of the copper wire? And given that, how do you know which is the ā€œrightā€ way round?

What cables have you tried? Have you tried all in both orientations? How many examples of each did you try with respect to orientation? And, importantly, please clarify how you undertook the tests?

Yes, into a block and switching off. My system at the time was CD555/NAC552/NAP500/SL2/nSub

Before deciding on the cable for my spur, I had 3 different cables in 15 meter runs over the floor & stairs from the CU to my system on the first floor. It took me weeks to run them in (mostly), swapping, and compare their influence on the SQ. My better half loved this period too btwā€¦ :roll_eyes: :slight_smile:

Before arriving at the 3 ā€˜finalistsā€™, I did a pre-selection with a # of other cables in short 4 meter runs from the wall to the power strip. Not completely accurate but this did allow me to roughly filter out the better sounding cables. There is a limit to what you can do at home, time, effort etc. The last 3 cables were from Kemp Electroniks, Furutech and Belden.

I have not found clear & consistent differences that either point to solid core or stranded, shielded or unshielded as beter sounding. Not as a rule of thumb that is. Same for the diameter but this might be related to the size of the system too. Most striking in this respect was Belden.

The well known, tried and tested Belden 19364 was part of the roundup. Shielded, 3 x 2,1mm2. Thereā€™s also an identical 4mm2 version. The copper, # strands, filler, isolation, everything is exactly the same. Given my good experience with the 19364 for power cords in many shapes, lengths and varying equipment for many years, I was pretty much convinced the fatter 4mm2 version would be the cable for my spur. Notā€¦ As in, not at all. The ā€˜skinnyā€™ 2.1mm2 sounded way better in every aspect. Logic and theory out the window. Amazing.

I ended up installing a 5 x 1.5mm2 shielded cable from Kemp Electroniks, providing the best SQ in my situation. Connected in pairs for phase and neutral so effectively 3mm2.

In my experience, proper termination, connectors, MCB and diff switch play an equally important role in the end result than the cable itself. If not more. Every cut, junction, split, connector or socket that can be avoided is an improvement.

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RvL,

Thanks for a fascinating write up. You have gone way beyond the call of duty in your experimentation! Yes I can imagine that your better half loved having cables trailing everywhere!

So interesting that you found the smaller gauge of cable superior - thatā€™s exactly what I have found. Itā€™s counter-intuitive but surely tells us, if nothing else, that resistance is not the primary factor for determining musical performance.

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Lots of interesting reading in this thread.

I would like to add that a dedicated supply for hifi although beneficial isnā€™t as desirable as a dedicated earth IME. However it is generally unsafe to install one on a PME supply ( which has earth and neutral bonded together at source ) the system that most of us are being supplied with. ADDING a dedicated earth to a PME system (via say several earth spikes for example) creates problems through ā€œoverlappingā€ not to mention that there could be instances where your dedicated earth acts as earth for your whole grid. No joke! We canā€™t just disconnect the utility earth and add our own either. My Electrician gave me a convincing explanation of why not.

The old TT system in rural areas was great for us hifi nuts. Live and neutral supply only with an earth plate buried close to the house. But even in those areas it is being phased out because of age related erosion to underground cables from house to earth plate.

I guess that we will have to just accept the realities or move to a remote spot in the country

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thank you for a fascinating report on your expts

small point - what does 5x mean in the quote above?

Thank you Jim. It means that the cable has 5 conductors (wires) of 1.5mm2 each.

I thought so.

What do each of the 5 wires do?

Earth, live, neutral andā€¦?

Thank you Pete.
Yes, I admit I went a little overboard on this. But my logic is simple; the mains is where it all starts. The foundation everything stands on if you like. Regardless the myriad of boxes and cables that follows. SQ left on the table here, is hard to repair or compensate further downstream.

This is my 3rd dedicated spur (ie house) and I enjoy to get it better every time. And the good part is, compared to boxes a well setup spur is not that expensive. When I add up all the parts + the installation of the dedicated earth by a specialised company, Iā€™m at 2000 -ish Euro.

Iā€™m qualified to install the spur myself, that helps too. After installation, a certified electrician needs to review and sign off on correct installation & safety. This is also required for insurance and all that. A good thing obviously. But if you get all the parts required, installation by an electrician doesnā€™t have to be very expensive. Typically itā€™s only a few hours work.

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Sorry - thatā€™s 2 wires paired for phase, 2 for neutral + the remaining one for earth.

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Do you remember the make, model, type and diameter of the cable, sockets and/or CU?

The CU was what everyone was recommending on the forum at the time but I canā€™t remember the name. The sockets were unswitched Crabtree. No idea about the cable brand. They were 10mm. Ring main less if I recall correctly and also with Crabtree sockets, possibly switched.

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I canā€™t find the UK report, but the problem is rife. Hereā€™s a report suggesting that up to 70% of cables imported into Uganda fail to meet safety standards.

https://www.graphic.com.gh/news/general-news/fake-electrical-cables-inundate-market-as-70-imported-brands-are-substandard.html

Determining which way round sounds best is easy. Listen to both ways. If this isnā€™t possible before installation I recommend installing 2 cables running in opposite directions, then choose the best sounding one. The extra Ā£10-20 is minimal compared to the total cost.

I believe JV looked into cable directionality and concluded that bare copper isnā€™t directional, but the cable becomes directional when the dielectric is applied.

I accept that itā€™s a bit of an assumption that for a given cable the manufacturing process wonā€™t change, therefore neither will itā€™s best direction. For this to happen the manufacturer would have to reverse roll km of cable just to get the labelling right for audiophiles. I canā€™t see this happening tbh.

Iā€™ve tried enough cables to know that some sound better than others. Obviously I havenā€™t tested every cable on the market. I stopped when coming across the Prysmian because it was the best sounding at a very reasonable cost.

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Thatā€™s a really helpful bit of research youā€™ve done there RvL :+1: Your method was almost identical to mine, with cables running over the floor for months on end. How the Boss let me get away with it, Iā€™ll never know!

I also tried multi conductor cables, but without much success. However, the conductors were larger than your 1.5mm^2 version which you found preferable.

I also agree that terminations, mcbā€™s etc are just as important, and joints are a definite music killers!

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I was interested to know which/how many twin & earth cables (of the same conductor size) you had yourself compared before choosing Prysmian?
And did you try them all both ways round?

I wouldnā€™t be concerned with your findings as, and Iā€™m 99% sure Iā€™m correct on this, Ken Kessler one of the UK Hi-Fi journalists (amongst other meanderings!), had a dedicated hi-fi room built with 3 wiring looms, 2 being specialist-brand mains cabling, one with bog-standard mains cabling - all set up as rings. The plan was to test the relative merits of each.

Weā€™re talking here in the days of 135s being Naimā€™s top amp, and I think Ken had a 250 (within a stock of kit) although he wasnā€™t a fan of Naim.

In comparing the cables, he asked a Naimee friend which was best, and their response was the bog-standard cabling.

(Apologies to Ken if incorrect).

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