Having finally taken the red pill and invested an inheritance into an ex-demonstrator 552 in my system, I have at once upset the lovely pre-existing 282 / 300DR harmony I had as well as open the doorway to levels of detail, insight and musical delivery I have never previously experienced and certainly beyond any degree of any expectation I had for the 552. Quite sensational!
There is however an excess brightness to the upper midrange at times and a couple of other areas that the increased resolution of the pre-amp that could do with balancing out, and I would be very interested to hear others views on the importance of a dedicated spur and / or a conditioner such as the new Isotek Aquarius V5 in getting the very best from the 552. My main source is vinyl from an AVID Acutus / SME V / Reference Ruby, connected through to the 552 with Chord Epic, and I have retained the old Signature Tuned Array DIN-XLR’s from my previous set up.
One last thing - do other 552 users get frustrated but the channel imbalance at very low volume? I have had a new pot fitted by Naim recently and the effect remains - I understand the 552 pot is unique and a little non-linear at very low level by design…
I rate a dedicated spur as a need/must have with this quality level of equipment. That would be prio 1 for me and see if there’s still a need or benefit from mains filtering/conditioning.
As @RvL mentions, at this level of system (well at any level really), getting a dedicated radial (or radials) installed along with a separate consumer unit for the system is very worthwhile. There are quite a few threads on this topic with plenty of advice from those who have gone this route so worth having a search for those.
I also think dedicated mains is important for the system. How long has the 552 been switched on and was it new? I ask as you may be experiencing warm up/ burn in which can affect the sound quite a bit.
It is coming up to about 12 months old, but I understand it saw very little action in the dealership, as they had access to Statement, which was the main high-end option demonstrated and used.
I’ll certainly investigate the spur option as a first step.
Interested in the many posts relating to dedicated spurs, however, these spurs must necessarily effectively split the supply tail from the property provision point. Why would noise from the original tail, not to mention that from all the other properties connected to the same phase in the area not propagate to the ‘new’ dedicated spur…… as RFI if nothing else, assuming the energy providers do not install incoming filtration on the supply side?
Or am I missing something?
UPDATE: Just updated my Isotek MiniSub II to the Aquarius Evo 3, and whilst not a night and day change, definitely a step in the right direction. Living in an 80’s property, plenty of mains noise from both within and without, presumably from those other properties on the same mains phase.
I wondered about this too. It seems unlikely to me that mains noise from other radials/spurs that make up the mains in a house, doesn’t propagate to a spur that originates from the same CU. It might be less though, I don’t know.
I think the improvement also (or even mainly?) comes from a better and heavier dedicated cable with better - and less - connections, better socket(s), resulting in a lower impedance etc. This seems to be an obvious improvement over the typical solid core stuff that lives in the walls. That is also directly shared with a # of other devices, appliances etc.
What RvL wrote. I will add that I have a dedicated earth for my hifi vía three large earth spikes buried and wired in spur type config in the garden. They are under an area topped out with gravel so easy to water during dry periods. The dedicated earth wrought a bigger improvement to sound ( lower noise floor ) than the dedicated AC supply itself in my system.
I have a dedicated earth from a 13m (40+ ft) rod straight down under my house providing a virtually 100% clean, very low resistance earth. The ground in the Netherlands/Amsterdam is close to a swamp so the conductivity remains stable throughout the year. The improvement was indeed (even) bigger than the AC spur alone.
I got it installed by a specialised company. They measure resistance with kind of a wired triangle measurement via two additional points in de ground some 50 feet away. Interesting to see that with every 3 ft. rod that goes down, the resistance drops. It’s about 0.3 Ohm I recall. That was 300-350 quid very well spend.
