I am looking at the ND555 upgrade. I already have one 555PS.
I have read a 2nd 555PS makes a good upgrade.
With this in mind how do you connect them ??
Am I correct in assuming use socket number one from each 555PS using the 2 Burndys that come with a ND555
Hope this makes sense.
Use the Burndies from the ND555.
Plug one into socket 1 of first 555PS and the other Burndy into socket 2 of the second 555PS.
…then enjoy! 
PS - the Burndy plugs are fixed so that you can’t plug them into the wrong sockets - which does help.
DB.
Thankyou very much for that. I may have to stack the two x555PS. Is this really detrimental.
Plenty to read about all this on here, just do a search. But definitely try before you buy as very mixed results on this.
Not recommended.
Compare the cost of a 555PS with the cost of adding another shelf, maybe… 
Good point Ian, Thankyou.
Might be easy - if you have Fraim, or Isoblue or similar…
May still not be ‘cheap’, in real terms - but then a 555PS is… ???
I understood this to be the case with the NDS, but not with the ND555. Certainly not in my experience of having two.
G
Think plenty to read up on this subject and as said mixed reviews, but as always only the user can decide if its worth it
Indeed, and I pretty much read it all before plumping for the second PS.
G
Heard the nd555 with both when i had my demo……did not take long to succumb.
Gazza I assume you took 2xPS ?
Yes i have two……for a few years now.
So it’s wonderful in your view. That’s great.
In my system it was essential - for me and what I required done well.
The demo at the Dealer showed the increase in resolution top-to-bottom over frequency range - obviously superior bass tightness, depth and note resolution - more open midband and expansive high end.
It was so silly-obvious better that in context of my system it was more than worth the extra cost.
Never looked back.
DB.
‘Plus one’, as they say.
G
i’ve had the chance to try the second one at home…the benefit were so obvious for me that you don’t want to roll back …however that it is precisly when you pull it out of the system that you get the confirmation that 2PS it’s a must with the ND555 (at least a must to try if not currently an affordable must)
It seems the general opinion is a def yes to 2xPS. Now I also understand how they are connected thanks to Darkebear above
Perhaps that triggers some broader questions, like a) what is going on here that 2 power supplies provide such an obvious benefit over one, (would three be equally incrementally better)? and b) does this suggest that more, or just more powerful, power supplies would benefit other parts of the system too - like a CD, tuner, NAC etc?
The ND555 source has proved very capable of higher performance when the fuller split between A and D supplies is made such that they do not share any aspect of the Transformer either - Naim do say the noise on the supplies measures lower when there is no load from the D (digital) supply being drawn from the same 555PS box as the A (analogue) supply.
In the context of Naim, offering A and D seperate cables it makes sense this is an optimisation of that highly capable source component.
Naim have always offered PS upgrades so it is not a big surprise they know this makes a difference.
Perhaps other items will not offer as much performance lift as with the ND555, as it is designed to be the best Naim could achieve for the price without going full-Statement crazy costs.
I lived for many years with the CD555 as source and found two 555PS a significant upgrade for that source - but I’d say the same on the ND555 goes further and there are deeper layerings into the music that open-up and get rendered in a beautiful musical way than I was before hearing with the CD555 - as great a source as that was in my system the ND555 took it to another level entirely.
Also with the ND555 I found a good switch feeding it (I use Ethernet Regenerator with a small Linear PS) makes a very significant boost to everything musical done by the ND555 - tighter and cleaner bass, more pace and liveliness/aliveness and open top-end - once heard you can’t go back to just a normal good switch. Try it and find out is best - rather than argue it is not possible…blah, blah - just try it and it is as obvious as the two 555PS upgrade - lower noise getting in or whatever.
For the OP - enjoy your journey with the ND555 - it has a lot to offer.
DB.