variable performance - what causes?

Thanks for the replies. I've been concerned for some time that I have variable sound but have tried to ignore this. That was until last Friday afternoon when my system sounded at its best and my wife came in from work and said how good the sound was. She's never commented before so I could see how significant the change can be. What I've always been tempted to do is purchase better kit to solve the problem, hence my desire for a CDS2, but now I think that addressing my mains may be a better solution to start with.

Brendan

Borrowing some isotek equipment tomorrow so will post about its effect.

Brendan

I've always been a bit dubiious about this on Naim kit. After all you have a Supercap which should effectively supply good power to the 82, if filters and the like were the way to go I'm sure Naim would have incorporated them into the designes of the likes of the Supercap and XPS.

Only if your mains is unusally noisy would I expect this to be the way to go.

Hi ARC and J.A.

I use a PP600 (not 300) and my power consumption is similar to ARC's. You might want to search under my name as I've posted on it 2 or 3 times.

Best Regards,
Mark Dunn

Well I decided not to try the QUBE once I found out the cost. It may well be worth the cash but I have decided to purchase a used CDS2 as a replacement for my CDI instead. I may take a look at power filters like the QUBE and PS audio 600 once that is in place if I still find significant variability. I’m hoping (without any evidence) that having a CD player with dedicated power supply may help smooth out bad mains days. Equally I realise that having an improved player may high light the short comings in my mains even further.

In looking for a used CDS2 I’m trying to decide if CDS2/XPS/52 is preferable to CDS2/XPS2/82. It is difficult to get the old kit together for demo so any opinions on the relative merits of these set ups would be appreciated.

Brendan

"It'll Shine When It Shines"

A separate spur (before the consumer unit if possible) will help.

It will not cure buzzing transformers and the supply quality will still be variable.

The biggest variable is YOU and your mood/level of tiredness.

I'm sure we've all had that listening session when the sound is blindingly good. Try to re-create it again the next evening and the magic just isn't there.

It used to bug the hell out of me, and I'd go into 'tweak mode'. Now I just leave it and do something else.

I guess listening to music is an emotive experience, so defies logic. That's the beautiful enigma of it.

Mariot,

In general there are less problems late at night and in the afternoon so I agree that this may indicate some mains issues and am considering a dedicated spur. However, I did have a spur fitted at my previous house which gave some worthwhile improvements but I still had some variability. This has lead me to consider a different approach to curing the problem and the consideration of a filter of some sort. I am not convinced that I want to spend so much as I can get very close to a CDS2 head unit for the same price and it is always tempting to buy better equipment even if addressing the mains is more pressing.

J.N. I agree that personal mood/tiredness has considerable influence on how I feel about music. What I do find though is that music has an ability to change my mood especially if it is on top form. This leads me to pursue some improvement to my situation. I certainly agree that sometimes it is better just to stop listening but I've not decide whether it is chicken or egg with respect to mood versus variability.

Brendan

I'm pretty dubious about this AC regeneration thing. As an (ex) engineer I have difficulty in understanding the benefits of converting AC to DC, back to AC again and then back to DC in the Amplifier. Why not just do the filtering and regulation on the DC?

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I'm pretty dubious about this AC regeneration thing. As an (ex) engineer I have difficulty in understanding the benefits of converting AC to DC, back to AC again and then back to DC in the Amplifier. Why not just do the filtering and regulation on the DC?

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Is it possible to be an ex-engineer

The benefits of regeneration are that one can produce a quiet supply, with extremely low impedance - the latter is a primary benefit, more so that noise IME.

Unortunately you can filter the noise on the DC sise, and even produce a fairly-close-to-perfect DC rail, but that DC PSU then runs from the mains, and mains variations then degrade its perfomance in clearly audible, but hard to measure ways.

It's so bloody frustrating....

Andy.

Andrew, thanks for the info.
It is very easy to be an ex engineer, you just have to get p****ed off with the poor wages, lack of respect etc, and to discover that there are easier ways of making (more) money.

Aren't you likely to run into the same problems in making the "perfect" AC supply as trying to make the "perfect" DC supply?

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It is very easy to be an ex engineer, you just have to get p****ed off with the poor wages, lack of respect etc, and to discover that there are easier ways of making (more) money

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I think that even if I did anything else, I'd still think and behave like an engineer.

What do you do know BTW, in case I end up the same

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Aren't you likely to run into the same problems in making the "perfect" AC supply as trying to make the "perfect" DC supply?

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Logically, I'm sure you're right to an extent. I don't feel you can ever eliminate the effects of mains, it's probably just another layer of isolation...

Andy.

Is the only solution to these problems more expensive boxes? That seems to be the solution proposed to anyone posting here. Has anybody managed to achieve satisfying results without reverting to type and spending more money?

"I think that even if I did anything else, I'd still think and behave like an engineer."

Andrew, you're right - I do still act like an Engineer, I just haven't done any circuit design for the last 6 years or so.

"Is the only solution to these problems more expensive boxes?"

In fairness to Forum Contributors, I don't recall much of this. Usually, if someone reports variable performance, they are forwarded to their resident sparky for a dedicated spur or are coached to try out some real stands

Dodgy mains evidence themselves through all levels of Naim kit, possibly even more so through the higher-level stuff. At least this seemed the trend with the olive boxes. Not sure about the new stuff which seems less sensitive than the old stuff.

- GregB

Insert Witty Signature Line Here

There is a temptation to spend more on equipment to deal with this sort of problem but most of the advice has surrounded optimising my current set up. I am considering a used CDS2 at the moment as the time seems right, I've had an unchanged system since 1996 and overall have been extremely happy with it.

What I have done that has made a very significant improvement whilst investigating this problem is disconneted and re connected all power, speaker and signal leads and reconnected. I can't believe that I have not done this more regularly, much of the glare I was getting has gone and I'm well chuffed. I could almost manage without changing to a CDS2. In fact it is hard to believe that a 9 year old CDI can sound so good. Thank goodness I purchased Arcs when they were £1675.

Brendan

Mariot,

I didn't really have a purpose to disconnecting and reconnecting. I started disconnecting to incorpoate a Pioneer receiver into my system, then I remembered a thread on this BBS stating that contact cleaning was a good idea so I just did that whilst I had my system switched off. This did have a positive benefit for me, I also bared fresh NACA5 and got rid of the oxidised bits that had been exposed to the air for some time.

Add to this the purchase and use of a lens cleaner for £15 and overall a satisfying and cheap process.

Brendan

I need a week or two to judge the long term effects. So far in 5 days of listening I've had no significant poor performance although my listening times have been similar. I used to be affraid of listening to certain albums like Division Bell as some of the electric guitars could be a bit shrill at the volume I like to listen at (around 9 to 9:30 on my 82). Now things are much better. My 82 is being serviced after Easter so that should hopefully, once run in, provide further benefits.

Brendan