Hi all,
I have an early NAP250 BD Serial #1647
I bought second hand about 5 yrs ago and I’m driving arc’s with great success
I was wondering about servicing and as I have no history could anyone have a look at the internal images and give an assessment as to its originality. @StephenPacker I believe you were a previous owner do you have any history that could help me?
Thanks 
It has definitely been recapped,check the big
Caps for date of production.
You don’t see any other code ?
For example, “9742” often means the 42nd week of 1997. Common variations include using only the last digit of the year, specific manufacturer codes, or letter-based codes for month/year combinations
Contact Naim support, they will have a record of servicing it if they did it. The only other official place to get Naim kit serviced is Class A, and they will also have records if they did it.
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@NeilS might well be interested to see the internals and advise whether it looks like it has been Naim/Class A serviced or not…
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36 th week of 2019
SIC-SAFCO (now part of Exxelia) date codes generally follow a 4-digit format indicating the year and week of manufacture (YYWW)
.
[image]Exxelia +4
Key Details on Date Codes:
- Format: Typically YYWW (Year-Week). For example, “1409” translates to the 9th week of 2014.
Yes 2019 caps, so a service shortly after that date.
I’d say it’s probably a Naim service, as I don’t think Darran likes to get involved with rewiring the rectifying diodes.
Regards
Neil.
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I know googled for noodles but found this re batch codes specific for 1979 era?
comments?
Technical Provenance (The “1936” Evidence):
Internal inspection confirms the presence of the original Sic Safco Felsic reservoir capacitors. These carry the rare factory date code 1936 LL144.
- 1936: Confirms the 36th week of 1979(September) manufacture.
- LL144: The specific batch/lot code for this era.
1979 caps would be silver or gold.
We started using that type of blue axial cap in the power supply boards sometime after 2010 I think.
Regards
Neil.
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Hi @NeilS
Are you referring to the small axial electrolytic capacitors or the large reservoir “buckets.”
How do you read out 1979 from the code 1936
instead of -2019 36 th week ?
As I understand due to the batch code it predates the more usual interpretation, but I’m only going on what I have been able to find out via google, AI (sorry). I want as honest an appraisal as possible given I have no paper history
As Neil sad the Caps didn’t look like that in 1979.
Give Naim the serial number of the BD Nap 250 and you will get the exact date of recap,if they have done it.
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Quote, not me…thought it may evoke some conversation?
“The “Batch” Reality
Naim was a small, artisanal factory in 1979. If their primary supplier (ITT) had a shortage, they would source the next best “Reference Grade” alternative. Sic Safco was a premium French manufacturer used extensively by Naim’s contemporaries (like Exposure and Musical Fidelity) and eventually became Naim’s sole supplier for the Olive and Classic ranges.
It is highly probable that your Serial #1467 was part of a specific 1979 batch where Sic Safco was used instead of ITT. The “1936” date code is a hard physical fact that cannot be ignored—it identifies the week of manufacture regardless of the color of the plastic sleeve.”
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According to my data, your NAP250 was built between April & June 1978.
Regards
Neil.
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Generative AI is not known for its accuracy. Sometimes right, sometimes wrong. If you want anything reliable from AI you need to delve deeper, ask more questions such as where it gets that ‘idea’ from, and evidence to back up. I would never rely on anything it comes up with without further research. Surely Naim is infinitely more likely to be correct with their own products!
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