Glad you’re feeling better and it’s all coming together! 
I would love to try bolt down 12 / SNAPS / 250 but never heard them. I had one opportunity to buy a set but didn’t have the cash at the time.
I did own the same as you and that worked very well, especially with Kans and passive Isobariks.
Either speaker cable will sound great, NAC A4 too - you’re just tweaking with a system you already enjoy at this point, so all good. Sounds like you’re on a roll.
Stay with NacA5 a much better cable than K20 into Kans .
I only heard 32/SNAPS/BD250 once and that was what made me fall in love to Naim sound (without the PRAT – never serviced before)
I think with BD12 the whole would be even more smooth and mellow, less resolution but make more focus on music enjoyment, even lesser hifi (eg a bit flatter); with snaps and bd250 it would sound softer, sweet and romantic yet retain a weighty voice.
As newbie came across from hifi world I’m very satisfied with this set – warmth, weight, soundstage, full control of speed (Kan MK1 reflects that really well). But with time I’m sure I would explore like you did! (A dream sets shall be 12/bd160, 32/snaps/bd250) at the moment this flagship set serves really well in my office.
Cheers finally I’m enjoying the music instead of analysing the details of sound.
My bolt down 160 had been serviced by Naim once before but the 12 was unserviced when I bought it. I’d say they had decent PRAT enough, along with the romantic midrange. Post Naim service, the combo was much more on its toes but retained most of the mellow warmth.
If you go for a K9 then I would also get a VM95E stylus as well. They are super cheap - beer money. Just thinking that with your Cirkus you might get away with it. It will offer some advantages over a low-wear K9, such as more vitality, more neutral, more open top end. If you can live with the inner groove distortion then I suspect you will prefer it.
Thanks for the head up! Just had another day of troubleshooting.
Again issues regarding the HF:
The newly serviced system seems too revealing at HF, no matter vinyl or digital from Dac V1;
Kan MK1’s HF response could be harsh from time to time;
Issue I found today:
when with Dac V1, my NJ326 boards sounded very well balanced, but the HF is too revealing and cause fatiguing;
I didn’t know the NA328 boards’ gain was turned to 9 o’ clock position which the HF was really emphasised. Such adjustment was also found affecting the sound of NA322 after some AB tests;
My Snaic 5 grey sounds weird occasionally at HF, especially when playing modern music. Not sure of it’s part of the ‘inferior’ part to the black. And it sounds slightly better when 328 is installed, when 326 installed it just causing issues. Maybe it just too old and oxidised inside;
The 322/5 boards got too high loading (470pf) and most carts will sound bright with it, part of the reason why even with vinyl it sounds so bright;
My solutions:
Will put the 326 aside until my system get fully burnt-in;
Using 328 instead. I put lot of time testing the best adjusting position for my taste, and I found the 1:30pm position is good: mid comes slightly upfront, without losing much air.
Lot of comments said 328 is a horrible design but found I quite enjoy that, with a soft, sweet taste of Naim sound like analogue. Now the hearing is non-fatiguing and enjoyable, even with the Kan MK1;
switched to Snaic black. Sounds warmer, sweeter, cleaner and better separation. Thinking to buy another snaic grey and see if the same issue happens;
put aside my current cart. Buying a Shure V15 Type III (400pF-500pF loading which is perfect for 322, my previous cart got similar sound signature) tomorrow at a nice price. I expect the bright issue will be gone immediately.
–
Summary:
After few days of troubleshooting finally found out causes the issues – a mix of everything. But part of the fun with vintage gears!
Beautiful
Most of what you’ve described is outside my experience, except having issues with Kans.
Anyway, glad you’ve got on top of it and hope it lasts.
The NA328 (variable line level) boards were designed with a buffer/filter circuit to deal with the early and awful sounding CD players back in the day. Instead of using the 326, you can bridge the pins using links, making that slot a fixed line level input. I think it’ll sound better this way. This is what I had done in my 72.
I have a 160 not BD
I have tried a 250 olive along side it is very good,
but I found the 160 sounded nicer,
I have a 160 too, also not BD and I am very happy with it. I have no intention of changing it.
It will be interesting to hear what you think of them if you are able to compare both.
At the moment It belongs to a customer of my Linn dealer. We know nothing about conditions yet. The other option Is a CB 250 at my Naim dealer. I’ d prefer the 160 though
You got a hi cap to go with the 250?
Probably asked you before what year is yours?
Mine is 71,
Not BD hence post '80
CB160 here too - not going anywhere!
