NAP90 Schematic

Forum advice within the AUP would be to contact the factory or your nearest service agent. Otherwise Google is your friend 

We'll leave that one there. 

Just out of interest how did you fry the outputs ?

Dylan, as James mentions above, you should contact the service dept. of the Naim factory.  DIY discussion is outside of forum AUP.  As you have just joined, please take a moment to read through the forum rules.  Thanks.

https://forums.naimaudio.com/to...ease-read-and-follow

Dylanthecat posted:

Hello All, My NAP90 has fried on both the output channels. Unfortunately I can not make out the specifications/ performance criteria of the components that I need to replace. I would be hugely grateful if anyone has a schematic/ circuit diagram that they could share with me. Many thanks Martin

How did it so ? Normally Naim amps are protected from overheating 

Regards

Roberto

Roberto, under certain conditions the very early NAP90/3 could get into almost a thermal runaway situation. The result was hot running and a browning to the PCB, although actual failure was very rare. It was quickly fixed by a small board and component revision and AFAIK Naim replaced the boards on any affected unit FOC right up until about 8 or 9 years ago, when apparent demand basically ceased and PCBs were used up.

This is, of course, different to "blowing" output devices through whatever cause, whether abuse, shorting, or otherwise.

Hi, I have no idea of the root cause of the failure, one side has gone and the other on the way out and blackened. It certainly wasn't as a result of misuse or abuse as the power amp/ pre-amp have been treated with kid gloves in the extreme. This is one of over twenty-five rigs currently owned on conditioned power supplies with regular soft start variac low load run ins etc. I suspect simply a MTBF issue associated with SMS designs. I suspect that new boards are the answer in all honesty. M

Martin, you'll need to get in touch with naim's service dept.