I have been looking for a CB 140. Found one whose serial number is below 200, which would indicate it was manufactured in 1982. However, the 140 was not introduced until 1986.
I realize a number of 110s were later converted to 140s, but this one looks as if it was born as a 140. (1) The knob doesn’t have the “marbled” look of early CB products. It still looks very matte grey. (2) The rear appears unaltered, e.g. no messing with the silver badge the name of the product is printed on, and the various labels that say “Southampton Rd.” appear to be original - they are still flush against the rear fascia, indicating they were probably never tampered with.
Can anyone explain this bizarre contradiction? When did Naim leave Salt Lane - in other words, does the presence of an original Southampton Rd. label rule out the possibility this product was originally made in 1982?
The possibility of it being a converted 110 was my initial hypothesis too, but all indications from the back are that it was born as a late model 140. The 110 conversions I have seen retained the original fuse holder, model markings (i.e. the badge still says 110), rear cosmetics, etc.
Is it possible that some 110 conversions had the entire rear panel changed out? Would seem unnecessary, but I have seen stranger things I suppose.
I would post a picture to make the discussion easier but that seems improper.
There were two different sized chassis used for the 110, the smaller one was replaced during a 140 update as the 140PS board wouldn’t fit in the short chassis. However, if this was the case it would have a full 140 rear label & IEC inlet with integrated fuse.
When we still had the original typewriter used for the small aluminium labels, we would type out a new one for “long chassis” updates. So an undisturbed label doesn’t necessarily mean much.
Only way to be sure is to look inside!
Bear in mind that the early NAP140 used different output devices - Sankens rather than the NA002s used in a later NAP110.
Question to @NeilS - If a NAP110 was given a NAP140 update, I assume it would not have Sankens fitted, but would use the existing output devices. This is how my own NAP110/140 is - NA002s on the amp boards but a new PSU board.
Yes, transformer would remain, speaker sockets were usually replaced with the more flush type. Extra earth wires added to the PA signal inputs (capacitor decoupled on the new PS PCB) which lowers the noise floor.
Otherwise, it’s pretty much a power supply stage change - separate reservoir caps for each power supply rail, rather than one pos & one neg shared between the PA boards. Plus extra smoothing on the preamp power supply output.