power supply quality in winter
Posted by: Emil F on 25 December 2004
In spring I made some upgrades and the system needed two months to break-in. In the summer I had an outstanding sound. Since October the system started to show some weaknesses like small lack of bass and depth.
After checking the whole system and analyzing the situation I came to the conclusion that the reason for the unsatisfying sound results in the last two months is dirty mains. It sounded excellent in the summer, but now I can't come close to this sound.
I have 3 x 6mm2 Live spurs coming from the basement to my CU.
I was using the first Live spur for the system.
During the last week I measured the following rates:
=====First Live spur//Second Live spur
13.00h////223V/////////225V
18.00h////228V/////////231V
01.00h////232V/////////232/233V
I replaced the Live spurs and now the second one is connected to the Memera CU. This gave me a little progress. An audiophile from the neighbor Macedonia told me that the power in winter falls to 195-200V! I think that it's a real problem for naim because we cannot use power enhancements. Last night at 01.00 o'clock I had 237V and the sound was OK. Christmas power supply.
Right now I can't see a solution for the winter.
Merry Christmas everyone!
Emil
Posted on: 25 December 2004 by London Lad
If I understand you right you have 2 or 3 volts difference between 2 spurs coming from the same AC feed? If so check your mains connections to the spurs, something is wrong.
Graham.
Not a lad any longer and not from London!
Posted on: 25 December 2004 by Emil F
Graham
Yes, there is a difference between the two spurs. Actually there are 3 Live spurs and one Neutral coming from the common CU in the basement to my apartment. One of the spurs is 2 or 3 volts less than the other two, when the power consumption in the block of flats is high. In addition there are two buildings under construction close to my block.
Emil
Posted on: 25 December 2004 by Emil F
quote:
Originally posted by TwoFifty:
Are these spurs coming from different phases?
Yes, from three different phases.
Posted on: 25 December 2004 by London Lad
Ahh sorry didn’t realize that you were on three phase. Ignore my previous post.
Graham.
Not a lad any longer and not from London!
Posted on: 25 December 2004 by Goldstar
Would it not be possible for Naim to make their amplifiers less sensitive to mains quality?
Just a thought.
Robert
Posted on: 25 December 2004 by David Stewart
I don't think you need be concerned about very small changes in the mains supply voltage. The European agreed standard specifies a nominal 230volts with a tolerance of +10% and -6% which means that any variation within the range 216volts to 253volts is acceptable.
A minor variation of 2-3volts should make no difference at all, these sort of variations happen all the time and power supplies have built in regulators to smooth out the small variations anyway.
The quality of your mains electricity may be worse in winter because of interference from power spikes and transients but you would have to persuade your electricity company to put an analyser into your circuit to determine whether this is the case.
If its unacceptably 'dirty' they might be prepared to provide you with a new circuit. Forum members in the UK have succesfully persuaded electricity companies to do this.
Posted on: 25 December 2004 by J.N.
quote:
Would it not be possible for Naim to make their amplifiers less sensitive to mains quality?
That's a fair question Robert.
I'm no tech-head but understand that it can be done. The mains can be 'synthesised' (as with the original Linn Lingo) and switched-mode power supplies can be used in place of potentially rattling toroidal transformers, but these 'solutions' rob the music of life, as far as Naim are concerned.
Rock and a hard place thing?
John.
PS - If you have a house near you, lit up like a Las Vegas Brothel at this festive time; that ain't gonna do much for your mains supply!
Posted on: 26 December 2004 by Emil F
I believe that 552 and 500 have excellent PSUs, which can stand better the unstable power supply. Maybe XPS2, Geddon and SC2 for the Snaxo have problems with the power supply quality. Could they benefit from a power conditioner? Do they have mains filter, which can cause problems? What about PS Audio?
I am missing the weight and scale of my 'summer system' and I must do something.
Posted on: 26 December 2004 by Emil F
quote:
i would also be inclined to only use one of your phases at a time to power all equipment, have you tried this?
Mark
This is what I do.
I can arrange a home demo with a power conditioner. My idea is to try it with the sources.
Emil
Posted on: 26 December 2004 by Emil F
Mark
A dealer in Sofia offers PS Audio products. He has P600 or P1000 Power Plant in the showroom.
Posted on: 26 December 2004 by naime
hi emil
be very carefull with 3phase electric supply
you have 400 volts beetween phases could be
fatel if you made a mistake i certanley would
not have 3phases feeding my equipment would
recamend you have your 3 spurs comeing from
the same phase
naime
Posted on: 27 December 2004 by Emil F
Mark
I have a Memera CU and 2 x 10mm2 spurs to the hi-fi. It helps, but it does not eliminate the problem with the dirty mains.
Naime
You are right. That's why I use only one phase for the Memera CU.
Emil
Posted on: 27 December 2004 by Emil F
Mark
I measured the voltage of the phases. This is everything I can do. One of them, which I was using, was 2 or 3 volts less than the other two. I switched to a better phase.
Emil
Posted on: 27 December 2004 by Goldstar
Hello J.N.
I really meant that the amplifier circuit could be designed to make it immune to power supply quality. Though I am sure Naim have looked at this area, maybe it could be improved.
There were endless articles in the Wireless World Journal on this subject.
Cheers Robert
Posted on: 27 December 2004 by Steve Toy
The spare capacity on our National Grid has been reduced to the bare minimum for short term profit to our privatised electricity industry.
There is a greater pull of electricity usage in winter - especially as electric ovens run more to cook the turkeys and other roast meats...
My Mum was complaining that a turkey leg remained uncooked in the middle despite allowing otherwise more than sufficient time to cook it.
Either voltages drop blow the Standard, or we get power cuts.
My hi-fi system sounds smoother but less dynamic as a result in the daytime.
Regards,
Steve.
Posted on: 28 December 2004 by Mick P
Steven
You said
"The spare capacity on our National Grid has been reduced to the bare minimum for short term profit to our privatised electricity industry.
The reality is that the Electricity industry is suffering from reduced margins since derugulation. They are mothballing plant and even worse, not buiding new generators.
The bad guys were chaps like me (industrial buyers) who forced the selling price down by over 50%. It was only last year that the price of energy rose after a 10 year downward spiral.
The price of electricity is due to increase sharply over the next 5 years, due to government interference.
It is imposing targets on the industry for clean renewable energy, which is expensive, so expect to see lots of windmills and also a resurgence of nuclear power. Failure to meet those targets will result in heavy penalties so expect your electricity bills to increase by around 8% pa.
The only good news is that gas prices are linked to oil and despite the current high, the price will almost certainly lower over the years. Russia and China are awash with the stuff and volumes are dictated by the west as part of the deal for financing construction of the wells.
Regards
Mick
Posted on: 29 December 2004 by Rockingdoc
The mains supply in our street caught fire on Christmas day. We had no power between 8.00am and 3.00 pm, a cold dark house and a very late turkey.
Back to the plot. They have dug up a long stretch, right back to the sub-station about 200 yards away, to replace smoking cable. They are still working on it, so I wonder if I should go out and tell them what cable to use?
Seriously though, I've been having big mains problems with the Naim for years. Fingers crossed this might result in an improvement.
Posted on: 06 January 2005 by Emil F
I did some experiments.
I tried a power conditioner: PS Audio P500. Once, when the power supply was very bad, it added some weight but sucked off the life of the music. In better days it is awful.
Second, I replaced the low voltage phase with a better one. I did more. I took the cable of another phase and made 2x6mm2 = 12mm2 to the CU. This is for the system only. Please note that I'm using the other phase as a cable only. Now I have 230V through this 12mm2. The sound is better.
Emil
