For some time I have been complaining and asking advice about the treble harshness of my system to Naim, local dealers and my friends. I upgraded 3.5/hi/62/90 through to cdx/112/hi/150 looking to cure a top end graininess that made listening a real pain. I thought there was a problenm with my cdx. Blamed RF interference and was pretty cranky. I even brought in a ton of other manufacturers' equipment to try and solve the issue and tried other interconnects and other speaker wire. My wife has not been impressed, as you can imagine. I previously helped other Naimees here in SW Ontario with power issues and one dealer felt strongly that it was still a power issue even though I was running two dedicated circuits (one for the cdx and other for the amp).
A couple of nights ago I went down and looked at the power panel and examined the grounding clamp. The pictures you see (thanks, Mike) are the appalling condition of the connector that attaches the panel to the water pipe and provides the house ground (standard electrical code where metal water pipes are used). I cleaned up the severe oxidation on the pipe itelf and replaced the clamp with a new copper one. Well, that was the solution not only to the treble issue, but also some other things that I had no idea were there, as I was fixated on the treble harshness.
Perhaps the system is a bit 'intense' now but truly unbelievable. Pinpoint location of instruments, a gigantic soundstage, incredible system 'blackness' and more and better bass than I have ever had. Every detail is there but without the harshness. I had no idea that
Naim equipment could sound like this.
My diagnosis is that the ground clamp severe oxidation caused a significant increase in the house ground resistance compared to the input neutral. This resulted in a 'neutral current' whose symptoms in the Naim gear included the graininess, background noise, susceptibility to RF, bass shyness and daily variability in the system. Perhaps this is not an issue where 220V is used, but after this experience, a high quality ground is essential to the health of your Naim system (perhaps of your sanity, as well).
Why I didn't figure this out before is just plain doofusness. I guess you'd better get the basics right before wasting time on the ancillaries.
Posted on: 18 November 2001 by Steve B
Not heard that one before!
MrI,
When I found a loose/poor Earth connection some years back my system just sounded flat and lifeless, not harsh as you describe.
Still, I'm glad you've sorted your problem and are now happy with your system.
Steve B
Posted on: 18 November 2001 by Christopher
Great to hear somebody fully satisfied with their system. Well done!
I'm running a CDX/PSX/82/HC/180 and I although I enjoy the system it never sounds anywhere near as good as I have heard it sound at Grahams. In particular there's a lack of detail, sometimes a lack of life and a very small soundstage.
I suspect that I could have a supply issue, as I live in a block of appartments, but I'm pretty clueless when it comes to all things electrical, so I've no idea where to look or even what to look for... would a whole block (c1900) share the same earth, or should each appartment be earthed separately? is there anything I can do to check out the supply and earth quality? Can anyone give some idiot-proof pointers?
Alternatively could this be due to the environment? Wooden floors, no curtains, a very minimalist room has resulted in some audible echo when clapping etc (I will be putting down a rug soon). However, if anything I'd think that this would make the sound MORE lively? 
Posted on: 18 November 2001 by Martin Payne
quote:
Originally posted by Christopher:
In particular there's a lack of detail, sometimes a lack of life and a very small soundstage....
Alternatively could this be due to the environment? Wooden floors, no curtains, a very minimalist room has resulted in some audible echo when clapping etc (I will be putting down a rug soon). However, if anything I'd think that this would make the sound MORE lively?
Of course, I can't comment on the mains, but these could very well be symptoms of Poor Room Acoustics.
PRA(tm) is especially likely where echo can be easily heard in the room.
cheers, Martin
Posted on: 19 November 2001 by Mike Hanson
I'm really happy to hear that you're finally getting your system sorted, MrI. It's been a long and hard journey for you, and I'm sure you feel very good now that it's working as good as you expect.
I've occasionally been known to scoff at the importance of grounds; I usually view them as more of a safety requirement than anything else. However, it's becoming remarkably clear that the ground is quite crucial for proper Naim operation. I need to check my own ground configuration now.
-=> Mike Hanson <=-
Posted on: 19 November 2001 by bam
Copper rusts
This is a great example. Presumably the earth for you whole house was very poor and was picking up cross-talk from the mains. Now you are safer too.
I wanted to take this opportunity to remind those who are making their own grounding systems to avoid using materials outside that rust. I'm not an expert on rust-free conductors, except that I know gold is one (sort of expensive, though!). Lead also oxidizes. Stainless steel or tin perhaps?
Posted on: 19 November 2001 by Mark Dunn
Hi all:
Bam wrote:
>Copper rusts
Now, you know what I'm going to say, don't you?
BTW, did you find the info' you wanted on the PS Audio Power Plants?
Best Regards,
Mark Dunn
Posted on: 19 November 2001 by Martin Payne
quote:
Originally posted by Martin Payne:
...could very well be symptoms of Poor
Room
Acoustics.
PRA(tm) is especially likely where...
Just a joke, really. It seems to me that many mickey-mouse companies assign a grandiose-sounding TLA (Three Letter Acronym) to some meaningless phrase, and then copyright it, patent it, or even TradeMark (TM) it.
Just having a Larf.
cheers, Martin
Posted on: 20 November 2001 by bam
Hi Mark,
At your prompt I went back and had another scour of the PS site for some specs for the 600. I can't find them. The closest thing to a spec I can find are the case dimensions.
It smacks of a web site created by marketing people: you know, lots of platitudes and exaggerations and no specifics. Words like "pefect sinewave" and "eliminates all harmonics" make me shudder. The sort of stuff I expect to hear on the Shopping Channel rather than at a serious equipment makers site. I did find some article where they do the "before" and "after" spectral plots - but even here they have an arrow highlighting the supposed elimination of harmonics but a big, wide spike at 800Hz is sitting there unexplained. By the way, just what is a "hospital grade" power socket?
Anyhow, I don't have any reason to doubt the electronics. I just can't seem to find a way through the bullshit to uncover the performance specifications.
BAM
Posted on: 20 November 2001 by Mark Dunn
Hi Bam:
Re:
>It smacks of a web site created by marketing
>people: you know, lots of platitudes and
>exaggerations and no specifics.
Yes, I know what you mean. Their web site started a metamorphosis about 7 months ago and it's got a bit twisted. However, I've gradually come to respect Paul McGowan for his technical know how and apparent business ethics. Try e-mailing them with your questions.
>By the way, just what is a "hospital grade" power >socket?
The ground connection is completely separate from the casing or fixings of the socket. The idea being that spark causing static or short circuits are less likely to occur and as hospitals have a lot of oxygen gas and other things like ether vapour floating around, this extra precaution is seen as a 'good thing'. Also, having the ground or earth isolated helps prevent back emf from flowing from ground to, say, an expensive piece of equipment (the machine that goes... 'PINGGGG' - it's the most expensive machine in the hospital!) and affecting its ICs.
Anecdotally, I sell capital equipment for a living (if you can call my meager existence a 'living') and I always tell my customers to install a separate ground for the PLC (Programmable Logic Controller) for the above reason. If they say "a ground is a ground is a ground", I end up having to measure the voltages between machine and earth at one end of the equipment and showing them how different it can be from a measurement at the other end. i.e the equipment's frame is acting like a resistor and developing a pd. And where do they normally earth the PLC case to.....?
Best Regards,
Mark Dunn
Posted on: 21 November 2001 by MrI
[QUOTE]Originally posted by bam:
The closest thing to a spec I can find are the case dimensions.
I agree about their site but I actually have a Power Plant 300. If is meant to be able to deliver 300 watts and thus is suitable for my cdx/112/hi/150 which draws about 150 watts when cranked up. Thew technology is sraightforward: a 300 watt audio amp drivin by a digitally-synthesized variable 50-100 Hz oscillator. Their multiwave capability allows waveform shaping. However, I have never heard an improvement in my system over not using it, even before I fixed my ground. However, I reported some time ago that it really can help out other electronics (like my vcr or dvd player).
By the way, just what is a "hospital grade" power socket?
The groung is completely independant allowing the sensing circuitry in any monitoring equipment to assure that the patient is protected. Normally an individual wall outlet is wired with an independant ground to the distribution panel.
Also, the copper did not "rust", as rust is as iron oxide. The above pictures show tremendous oxidation on the clamp. The clamp itself is a zinc alloy, the bolts steel (rusty), the ground wire copper, and the water pipe lead. A little summer condensation in a cool basement and a ton of galvanic action produced that yucky result. So the decrepituded ground severely effected even "perfect" dedicated power. So look at your own grounds and adjust accordingly if the clamp and pipe look grungy. A copper to copper joint should not be sensitive to galvanic oxidation, although you might see some blue-green copper oxides.
MrI
Posted on: 22 November 2001 by bam
Main Entry: rust
Pronunciation: 'r&st
Function: noun
Etymology: Middle English, from Old English rust; akin to Old English rEad red -- more at RED
Date: before 12th century
1 a : the reddish brittle coating formed on iron especially when chemically attacked by moist air and composed essentially of hydrated ferric oxide b : a comparable coating produced on a metal other than iron by corrosion c : something resembling rust : ACCRETION
2 : corrosive or injurious influence or effect
3 : any of numerous destructive diseases of plants produced by fungi (order Uredinales) and characterized by usually reddish brown pustular lesions; also : a fungus causing this
4 : a strong reddish brown
