If you wish to invite me to listen to yours we could get it down to how the music sounds. I only have the 552 for about a week if you want hear it.
Phil
That’s kind Phil. I’m going to avoid listening to a 552 at all costs! What I don’t hear can’t hurt me (or my bank account) 
I thought the 552 had an internal brass sprung suspension to help isolate it from external effects. Does its sensitivity to exact positioning suggest that the internal suspension isn’t as good as it should be? Just an observation…
1 Like
All I can say - my 552 sounds more enjoyable on my full fat Frame (top shelf) than the top shelf of my non Frame rack…
Hi Dave, Well I’m prepared to believe that with experimentation as suggested by DB I don’t need to buy Fraim which also hits the bank account very badly! I’m willing to give it a try.
What 552 does is to extend the frequency range at both ends and more accurately reproduce the source to reveal the music better. Clearly vibration of the circuits needs to be reduced and vibration will limit and interfere with the ideal performance of the box.
What the physics suggests is that when the glass is damped natural modes of vibration will be affected. After all the glass could be played as a musical instrument. This will probably enhance other natural modes and create different modes. We want the energy to be dissipated where it does the least harm to the music. It is fair to say that it is only vibrational frequencies present at the feet of the box that can cause problems. With a computer these could be modelled.
Phil
Observation suggests that the vibrational modes of the suspension are relatively low. The glass is probably quite high.
Phil
‘Help Isolate’ is the key phrase here. Things are cumulative and not absolute. People think if you spend enough you get ‘perfect’ but you get better - a lot better but still does not mean it is now totally insensitive to placement and you can do as you wish with it.
It gives the 552 a welcome boost in isolation which IMO assists it having the clarity it is capable of revealing - the lack of smearing of the trailing-edges of every note over and masking the quieter notes following. It opens-up the mesh of musical sound and was the first Pre I heard do this and give access for me to a new realm of musical insight.
But just as good placement helps the 252 it still does with the 552 - just that the latter is capable of more.
The internal suspended sub-chassis ideally likes to have the external case lessening as much vibration as possible before the internal suspension further reduces it. Preferably the vibration of the 552 on the rack will all be above the internal suspension frequency.
Careful placement allows optimization of it all - but if one is happy then leave it alone as it is - this was only in answer to a possible problem raised.
DB.
1 Like
I pulled out my ND555 to the Fraim edge which was centred before .Interesting difference to those subtle nuances of music…need to move around a bit more.
Interesting, I will move my 272 to the front of my Fraim once the wife has gine to bed and see if this makes a difference.
yes indeed MDS, that also my finding too… although I like the 552 very much indeed, for me the real magic comes from the source…and that is where I would and have spent the most money…
Although the 552 is a completely difference league to the 252 and 282, but still I found that source first still applies for what I value in musical replay…
1 Like
Would the ND555 also be best with its front panel at the edge of the glass. I am sure
someone has tried.
Yes, thats what i just tried…particularly on acoustic, female…rsther than rock. But i need to spend some more time on this over the weekend.
@Clive gave me some positional information for the cups relative to the front of the glass and sides
‘My equivalent measurements (front of glass to front of cup) are 315mm and 9mm. Edge of glass to side of cup about 5 or 6mm. ‘
So my setup under the box feet at the front was not the way Fraim positions the cups. It seems Naim don’t advise on where to position front of box relative to front of glass.
One thing that did emerge was that the depth of his glass is 338mm whereas I picked up a figure of 400mm (width 452 and thickness 10mm) from someone on the forum! This means the way the rear corners can naturally vibrate is a bit different, but the rear cup has a greater range of positions.
I would not like to give any definitive feedback on effect on SQ yet but I suspect the front cup position affects the voice higher harmonic frequencies.
Whatever it does a 552 is better than a 252 IMO.
Phil
For whatever reason (tweaking wise … ), with all front cups out wide and forward, and boxes on the front edge it is delivering a brilliant soundstage, which of course means that all instruments and voices are sounding so natural and vibrant. I suspect that this is the secret of full fat Fraim. I’m sure I could iterate further, but more than content.
Far (at least 20mm in any direction) away from this position there are reductions in the above characteristics.
From my wife point of view I can listen at lower volume levels because I get enough of an emotional response.
I still plan to go back to the 252 before making a decision.
Phil
What are your sources…?
I see you are using non-naim power cables for the Supercap DR and 300Dr…
After testing a few of them I came back to Naim power cables (even the standard ones)…
1 Like
Innuos Zenith Mk 2 into nDAC + 555DR via Audiophilleo 2 + PurePower. I also have CDX2 into nDAC but liking the convenience of this and not having CDs everywhere.
Phil
Phil, if you are hearing improvements with the 552 by repositioning the cups and the black boxes, then the 252 should logically reflect that improvement when it comes back.
I think you said earlier that you will get an opportunity to do back to back comparisons of the 552 and your 252 (both warmed up) in your main rig. That will be the acid test.
I will be very interested to hear your findings, and hopefully with the repositioned cups and black boxes, you won’t need to resort to full fat Fraim.
1 Like
I must update that. I have Powerline on 552 and 300. I still have the Isotek on the 555 DR and Aria. Who knows about the 555DR in the future. The two PLs came with boxes so if I stick with the 252 I may have to buy one.
Phil
Cheers. When testing the 252 again, maybe it is worth using the Powerline?
1 Like
Hi Nigel, yes I think the position of these cups may have introduced the variability as I’ve changed things because I never thought to fix their position.
It’s so annoying when one moment the music sounds all you could want and then it goes. I don’t want to fiddle, but perhaps ultimately you learn more (than that fiddling is not a good thing). I am a scientist and that is how we learn! But scientists use good instruments to measure things, and I only have my ears.
It may be the mains noise from the load drawn by the commissioning of the big incinerator.
The 4 pin SNAIC did not come in the post today so can’t start the 252 warm up unless I do it with no input or output. @Richard.Daneis this safe? Thanks.
I will report back.
Phil