252/sc -> 552dr

Since pushing the button on a 552DR my 252 has been sounding utterly sublime, better than ever. Typical innit!

The 552 will arrive in a month or so, straight from servicing. I’m wondering what to expect from day one. Should I prepare myself for initial disappointment until the burn in takes effect, and if so how long until things start to settle down? Is it best to leave the system playing continuously, and if so does the volume level make any difference or can I just leave it right down whilst not listening?

Or can I look forward to a major uplift straight away? And if so what can I expect? Be good to hear from anyone who has made this change with a 300 (non DR).

Is cable dressing more or less important than with the 252? With two stacks of three I find it impossible to get the burndies off the floor.

Of the many upgrades I’ve done this last year, this is the one filling me with the greatest sense of anticipation.

Sorry for all the questions and not expecting anyone to answer all of them! It’s nearly Christmas and I’m feeling like a kid again :smiley:


Much as I’m likely to kick myself, I’ll be watching your thread with interest, lol.


Like a moth to a flame :grimacing:


I upgraded from a 252 to a 552 earlier this year it was immediately apparent how much better the 552 was the music just opened up with incredible detail bass control and soundstage etc etc.

Months on it still puts a smile on my face when I play something that I have listened to many times over then listen to it on the 552.

Enjoy your new purchase.


Music to my ears…

Lol…thankfully the pleasure of my 252 at least dampens the sparks!

I did just this recently, partnering with a 300DR.

I am now a firm believer in ‘burn in’; for me, the 552 has evolved more than any other addition. Yes, there was terrific speed and command that I had never experienced, but with it came a brutal upper midrange stridency that was not pleasant nor especially musical. Hastily casting around for aftermarket cabling to try to tailor the sound more to the sublime 282 / supercap I left behind, I needn’t have bothered as the sound over the last few days has become even, musical and absolutely sublime. Huge soundstage, staggering dynamics and thoroughly consistent.

These changes have taken many weeks so be prepared and expect a bit of a ‘rough ride’ if my experience is anything to go by. Oh, and you too may notice a fairly dramatic channel volume imbalance as you get very close to the volumes minimum travel.

Good luck! For me, it was worth it all the way…


It’s a wonderful amp. Funny how I’m only now hearing just how wonderful it is as we ready to part company.


Thanks and that’s very reassuring to hear. Did you leave your system playing 24/7 to expedite the burn-in? Must feel like you’ve struck gold now that it’s settled.

When I went from 252 to 552 it was an immediate uplift. More life, more vibrancy and a more natural, engaging presentation.

Although my 552 is non DR and pre loved, there was definitely a settling in period. To start off the 552 sounded great but warts ‘n’ all kind of presentation. Over time things became smoother without losing any of that wonderful vibrancy.

I would expect your 552 may take longer to settle in as yours will have new caps installed during the service. Don’t panic if initially the 552 sounds a little hard and strident at times, it will greatly improve.

Both the 252 and 552 will reward you for time spent setting up and cable dressing. Try to get the Burndies off the floor, even if you have to resort to the odd hook, elastic band and pipe insulation. It is worth it, and once it is done you can forget it.


Bumpy ride for me, took ages to really settle down……

Worth it in the end



It was powered up but no, we just played music when we wanted to listen in the evenings and weekends, so full-time it may well mature more quickly.

One thing I will say is that I very very quickly swapped out the stock DIN-XLR’s for Chord alternatives as this was a massive benefit to my ears, but fully appreciate that some may well prefer the originals… Good luck!


So interesting to hear others experience the same transitions with time and that, thankfully, all seem universally agreed that it becomes very very good with time!

I’ve just upgraded from a 252 to a 552 DR, although admittedly, my 252 had been recapped 3 weeks before I bought it (about 5 months ago), and the 552 was a pre-loved one (and so well burnt in).

To me, it was immediately apparent that the music was more “there” - on vocal tracks, I found myself thinking that the singer was in the room more often, there was more detail, and the overall experience was more engaging.

I’m running mine in a single fraim rack, with a non-DR 300, so cabling is a bit of a mess. I might strip everything down in the new year to see if I can make it a bit tidier, but I suspect it’ll be small, incremental gains rather than a revelation.

Enjoy the journey - it’s going to be a fun ride!


Not sure if its relevant to you but I replaced the 82 with the new 552DR in a second system to run in. It ran in to a non DR 250 and gave an immediate improvement and sounded similar to the scDR/252/300DR in the main room. Ran it for 110 hours volume around 65db. When I moved it in to the main room with the 300DR it took a couple of days before I felt it had settled. It then seemed to improve almost imperceptibly until 8 days later (this Monday) I had a lightbulb moment and suddenly it just sounded ‘right’. Whether that was me or the 552, but it does sound a big improvement over the already excellent 252 it replaces.


Ignore as best you can all the stuff about run in. Just play lots of music😎


Indeed but the op was looking for confidence in his purchase. I was much the same and all I can say is that the 552 gives a more complete sound than the 252, but then it should for the additional cost.

1 Like

Hi Stu, I have a very similar system to yours. CD555 instead of NDS and the rest is the same even the speaker cable (which is one of my all time best buys). The 552 will sound better straight away with many more layers revealed in all aspects of a recording. You are in for a treat, just enjoy the journey, take your time and listen to how things evolve without rushing to get to the run in stage too soon. You will be amazed at the extra detail coming from your speakers gradually, more detail in bass, mid and such an open top end! Enjoy!

1 Like

My new 552 replaced a 252 & SCDR and is about 6 weeks of steady use into its life. I can report that out of the box there’s an immediate improvement with a much more nicely defined bass and a nicer spread of sound. From the off you’ll notice a definitive improvement in line with the concensus that surrounds the 552 on here. It also has a more useable volume range than the 252, low volumes excepted - see below.

6 weeks in and it appears to be settling in nicely with a sense of more of what stood out in the initial improvements. I cant say mine’s gone through phases of sounding awful or being a dreaful disappointment, but a lot of the time it’s been on in running-in mode on Radio 2 and not in-depth attentive listening. At present it’s very good and noticeably better than it was fresh out of the box.

Brace yourself for the Balance problems at low volumes. It’s a quirk of Naim that the 552 seems to suffer most, and the solution appears to be to go without for a few weeks and send it back so that a better one can be fitted.

1 Like

I haven’t noticed the balance thing, just turned the 552 down to 40 db and no balance issue.