Same for me.
Mij29, this is strange for me. The 552DR will sing with a 300DR beautifully and emotively. It’s a walk-over over the 282… so something is really amiss.
If it were my 552DR, a reference level pre-amp, and that imbalance is inaudible or negligible, I could accept it but anything else, it would be a send back immediately to Naim for another round of checks to make sure it is working flawlessly as it should.
I put myself in your shoes and feel your discomfort and frankly, it cannot be that your 552DR doesn’t reach out as emotively - and much more so - than your 282.
If you have a vertical stack, the EM fields from those large transformers in the power supplies will only emanate upwards, so you have two large transformers to contend with, the 300PS and the 552PS… hardly ideal for the sensitive electronics in the head units above. If we would make the effort to separate them well away from one another, Sir [tall Fraim spacers], and from the sensitive head units, that will help our system “flow” so much more. I have found this to “unclog” a Naim system and its sound.
Cable dressing is a downright pain in the arse, but it’s imperative for a sensitive system already approaching the reference level in your home.
Never least, room acoustics for me.
There is no other way around these collective touchpoints unfortunately. I feel your pain and am just trying to help you get your system to sing, as it should, same with all our friends who have posted here.
Something would be amiss with your 552DR, Sir if it still feels unemotive after you’ve done all the above, and I would get the unit back to Naim.
The last thing I can think of, is the dedicated power spur for your system - without good juice, the system just fails to open up.
I wish you speedy recourse for your lovely 552DR!! And to be blown away with it. Patience is the mother of all hi fi set-ups.