Has anybody tried 2xPS with the 500?
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Thanks James.
I am listening and undecided, but am hearing a lot to like. Have it for a few weeks - the acid test will be moving back to just one (as it was with the 2nd PS on the 555). But right now I am having enough fun to leave it in situā¦ this system grooves!!! 
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Hi Robbo so are you using to Nap500 power suppliesā¦by just simply plugging in one supply for each sideā¦and nothing else. I read somwhere that there were earthing issuesā¦
I may be wrong but I thought @RichardDane said Naim felt that two ps didnāt really work.
Initially it can sound really good - in a very "hifi-ishā kind of way. However, after a while you then realise thereās something not quite right. See here;
This is where I think Naim could do some researchā¦I am sure it could be developed I am also equally sure that you are correct its not just a question of slapping anther supply on. What would be good about this approach is that it would fit in with Naimās modular ethosā¦and possibly give a closer stepping stone to the Statement. I suspect the grounding in a shared chassis is
an issueā¦maybe an earth link between the 2 psuās could helpā¦development, development, development - come on Naim. I know the 500 is a niche product, conversely there must be quite a few 500ās out thereā¦and such an upgrade would be tempting to most 500 ownersā¦
It would mean developing the individual power supplies for purpose as mono units. I recall Roy mentioning that he felt that there were likely āparasitic artefactsā from the unused side of each power supply.
Interesting makes senseā¦maybe you could keep the same basic psu design which is excellent but combine the outputs with a mini internal link bus bar arrangementā¦basically allowing the psu to act as one huge power supplyā¦all future 500ās could have this as standard. Existing owners maybe could exchange there 500 psu (which could be updated in the future) and get 2 new psuās ā¦ for say 12-14k ā¦ just a thoughtā¦
Soldš
Thatās what I thoughtā¦how many 500ās have been sold over the last 22 yearsā¦I am sure a good percentage of owners would be interested ā¦ not only that it would refresh this fabulous amplifierā¦giving excellent publicity.
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Sound like a great idea. However, something tells me it may not be quite so simpleā¦
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It never is!!! this is the genius of Naims patient and fastidious development ā¦linking it up would probably generate huge hum ā¦although in theory the psu would be nice and balancedā¦come on Naim dust of the 500 and give it some develeopmentā¦
When my brother worked at Heybrook helping design and build there amplifiersā¦they took the P100 and gave it twin supplies totally separating - separate transformers and separate rectification and capacitors. My brother said the same HiFi impact was great but something was missingā¦ there was no parasitic redundancy in their implementation - strange, however if memory serves me well they kept the single board and cut the tracks to separate the power railsā¦ I will ask him about how it was configured and tested.
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So why no such problems when you add a second 555ps to the nd555 or cd555, as surely its very much the same?
The 500 is mono design and split into left and right and i would have thought the power supply is basically 2 x the same in one box
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Thats what by brother thought when he separated the P100 amps to accept twin suppliesā¦it worked but sonically something was not quite rightā¦ Obviously with the 500 you have huge redundancy as one psu supply is left unused if you use the psu unmodified. That can leave the transformer a bit imbalancedā¦I suppose. I think doing surgery to the psu may be possible to link it together to form one mighty power supplyā¦should be fairly straight forwardā¦
Not being an R&D engineer I have no idea, but I would hazard a guess it may be down to the two sections of the 555PS being for different things - analogue and digital perhaps? Or perhaps something that just affects a power amp?
Like you Richard not a clue really, i just know that the 500ps looks like it has a few windings from the transformer that feeds 12 big caps, that all look the same onto one board that also looks like its 6 x the same. That to me says that it split 3 to the left and 3 to the right.
So running 2 x power supplies and each only then using half the internals, if that gives you extra reserves as far as the transformer is concerned i dont know as like i said it looks to have a few windings on it, so i guess it wouldnāt as part now wouldnāt be doing anything?
