Naim Nait 2 CB LED Board Need Help!

hoyhoysum

Member
2008-10-19 11:20 am
Hi!

I just got myself a beauty, a Nait 2 recently. Cosmetically it looks good however the facia led fails on me recently. Upon opening up the case, i found that 8 nos green transparent LED mounted on a strip board drop by a resistor 8k2? I change all the LED and it works now. However it flickers according to tHe beat of music. It looks kinda cheap and i figure that it must have been modded. As i have none to compare, can anybody let me know the original how it looks like. A picture and some description is most appreciated. I would like to mod it back to the original condition..

Thanks in advance!
 
I don't recall my NAIT 2 having such a feature, but the picture i have says maybe it did.

dave
 

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Thanks for the photo, looks like mine has been modded and it is not original.
How many leds are there and how does the led array looks like?
Do your led lights dimmed when requires to handle high dynamic levels?

That amp was a long time ago. I don't recall it having anything fancy LED wise from the front. On or off.

dave
 

hoyhoysum

Member
2008-10-19 11:20 am
As for the "disco" light led i believe it must be the constant current source. Could it be the PSU caps, 6800uF 25V rubycon caps getting old? Before attempting any further diagnostic i would like to hunt for the led array fisrt. However i do not know how the array looks like, let alone the numbers of leds?
 

robmil

Member
2004-06-11 3:55 pm
London
Hi

I don't think your one has been modded. I have had 2 of these units from NEW! The first one which was about 6 months into the production cycle blew-up due to an electrical storm nearby, the second one about a year later looked quite different inside. The first version of the Nait 2 looks more like a Nait 1 inside.

I would go for the filtering caps first but I cannot remember if the 8K resistor just comes off the transformer and not post filter caps. The NAP140 onwards have their LED supply off the transformer.

Check out your filter caps first and upgrade the regulator while you are at it. The output trannies are the equivalent of TIP41 so watch your load carefully, anything more than a pair of headphones or a pretty 'easy going' loudspeaker WILL take out the output stage!... as it heats up very rapidly under harder loads. Look for dark PCB areas near the emitter resistors and output section. It is a poor choice of output trannies by NAIM. I'm sure they could have fitted something a bit bigger and made an adequate heatsink, but I suppose the point was to make an amp that would drive a cheap pair of $300 loudspeakers.
 

hoyhoysum

Member
2008-10-19 11:20 am
I just wrote to Naim and they are unable to help me. I have to get the parts from my dealer in my country. That will be the last thing i will do as the cost of parts will be exhorbhitant. I rather diy it myself using stripboard/ veroboard. All i need to know is the numbers of led required or a photo showing how the led array looks like.