Hi
My first Naim system is being installed, at home, by my dealer this coming week. What is the best way to get it to “break-in” and for how long?
SN3, Spendor A4, Hicap DR, CD5si,ND5XS2 Rega P9. Chord speaker cables.
The Rega P9 and speaker cables are retained from a former system. Everything else is new.
Just leave it always on.
Welcome to the club!
Your system should sound good right from the off, but will benefit from having music played through it for a good while. I’d recommend having a CD playing quietly on repeat when you’re not actively listening to it, 24/7 if need be. There will be differences of opinion on exactly how long you must do this for, so my advice would be to keep doing so for as long as you hear improvements to the sound.
Usual Naim advice is to leave the system powered up at all times. If that bothers you, don’t do it, or try it both ways and see if any difference bothers you more.
Enjoy the tunes!
Mark
Just play it leaving it on keeps things charged and to temperature but to work things out just build up volume exercise gradually.
My SN3 sounded great out the box at room temp and when you get familiar it will get better. 
Exactly the same situation with mine.
Have you posted that on the wrong thread?
Oops, I do believe we have!
Apologies yes. 
Thanks.
Just leave the radio playing on the ND5 for a few days.
For best performance i’d be inclined to ask your dealer to make up some decent lengths of NAC A5 and use the SA8 speaker plugs that come supplied with the SN3. Sell the other cables to off-set the extra cost if need be. As for running in - it’s advised to leave things powered up and use as normal. Over the first few weeks the system will gradually settle down & run-in.
It has been almost two months with my first Naim system. I switched to Chord Shawline one month in, connecting cables between my SN3 and both my ND5XS2 and CD5Si. The SN3 has a HighcapDR. Using Isotek power block and power cords. Rega P9 with Exact MM. Spendor A4 speakers.
Sometimes the system sounds spectacular. Great PRAT. Natural tonal balance. Good imaging and soundstage. Very not hifi in the best sense. Other days just meh. Not engaging and not defined.
The better days are starting to be more frequent, but there is still variance. Is this to be expected? Also for the most part Qobuz sounds better than Apple Music but not always. Also within a Qobuz album, some tracks sound much better than others.
Since this is my first Naim system I feel like I am on a sonic roller coaster. Very confusing.
Nothing special required to ‘burn in’ your system. Just leave it permanently switched on and use it as normal.
Your introduction of the Chord Shawline cables will have confused things. IME Chord cables take some time to burn in, and the effects are exactly as you describe.
It can all be a bit disconcerting and worrying for anyone not familiar with these effects. Don’t panic. Just enjoy the ride. It will all come right in the end.
Hi Jaybar
When it sounds not very good have you tried playing a favourite record that you know has sounded very good in the past ? Sometimes a pressing or file is just not made very well my system can sound wildly different from one record to the next.
The cables that come with Naim kit are really good. Why have you swapped them all out?
This may well explain your dissatisfaction.
We found the ND5XS2 took several weeks to get on song, after that its smooth, detailed and has the older Naim boogie too!
Martin
Wow, that’s some start
Looks like a great setup, however I would question a CD5Si with such a potent amp provided its the main source ?.
A bit unbalanced I may say.
I do know its the only Naim CD player in their program, but its entry level 5-series.
A Naim CDS3 or CDX2 would be on amp level but these are no longer available new, service support might be an issue too.
If you are able to change for a Rega Saturn or Roksan Black, maybe the new Hegel, these would be on amp level.
Nice to s hear P9 decks are still in use, I wonder why I sold mine long ago.
I suspect that you are trying to listen to the system and not just relaxing and enjoying the music. Things will improve for the first little while but it should be well settled by now. Mood has a huge influence on how enjoyable things sound. Just stop worrying about the system, and everything will sound much better.
Well Said 
New speakers will take some time to loosen up. Will need more running in than electronics from my past experience.
……and need to be played loudly for at least short spells to really loosen the cones.