NAD C 300 AMP + Smoke = :(

[DesignerPaul]

Hello all, first up I have to say I know very little about audio equipment so please go easy on me!

I have recently been given an amp (NAD C 300) and some (what I'm told are) nice speakers, that had both been working but kept in a loft for maybe 4 years. The plan was to run the audio from my computer through the amp.

I connected the computer (Intel 2 Core Duo iMac) to the AUX input of the amp from its "Headphone Out" socket. I was careful to turn the volume right down on the computer before slowly going to about 50%. All worked great and sounded superb for about 30mins. I turned the volume down on the amp walked away, came back about an hour later and the amp seemed to have turned itself off. On trying the power button the LED next to the power button flashed red but then died. I tried once more and a whisp of smoke came from the amp and died completely, no LED.

So my questions are. Is this my fault? Someone now tells me that I should only use a lineout to connect to the amp as the headphone output will be too strong? I don't think my Mac has a lineout however? What should I have done?

Also is there anything I can do to diagnose the problem? I'd preferably like to have some kind of idea before I take it to repair. Are these things cheap to repair and is it even worth it?

Any help would be much appreciated, sorry for all the novice questions!..

[jaycee]

Well you hooked it up OK. I have an iMac and it's output port can sense the difference between a line out connection and a pair of headphones.

My guess is, if it's been in a loft that long, its gotten dirt, dust and perhaps moisture in it, and that has killed the amp. Seen that before.

On an amp that old a repair shop will probably say "not worth it mate". Don't take it to a TV repair guy - they will make a royal mess of it!

It doesn't say where you are in the world, but if you were in Norwich, UK i would have been happy to take a look at it for you.

[DesignerPaul]

Originally Posted by jaycee

Well you hooked it up OK. I have an iMac and it's output port can sense the difference between a line out connection and a pair of headphones.

My guess is, if it's been in a loft that long, its gotten dirt, dust and perhaps moisture in it, and that has killed the amp. Seen that before.

On an amp that old a repair shop will probably say "not worth it mate". Don't take it to a TV repair guy - they will make a royal mess of it!

It doesn't say where you are in the world, but if you were in Norwich, UK i would have been happy to take a look at it for you.

Ironically I just picked them up from Norwich and have taken them home to where I live in York, though thank you for the offer! I would definitely like to avoid the "not worth it mate, get a new one" attitude since it was generously given to me and I wouldn't feel right to just throw it away. I'm not sure I will be back in Norwich for a few months however so I think I will have to find someone up here..

I opened the amp up and can clearly see a black burn mark around a capacitor (marked "c 718").

http://dl.dropbox.com/u/3454522/NAD1.jpg
http://dl.dropbox.com/u/3454522/NAD2.jpg