Up in smoke

Yesterday we had some friends over for dinner and put on a CD.  A couple of minutes later the stereo let out a quiet pop and a large cloud of nasty dark blue smoke.  It was nasty stuff.

I turned everything off and figured out a backup plan for listening to music that evening.  Today I investigated using my workshop speaker.  The left, right, and center channels were fine.  When I plugged the speaker into the rear left channel (one that I've never used!) my speaker didn't make any noise, but it did glow like a light bulb.  Not good!

Took the speaker apart and luckily it is just a slow blow fuse that died.  I can replace that.

I took the receiver apart.  I'm stuck with two options:

  • Replace it.  This is sad because it was expensive and only about 5 years old.
  • Remove the surround amp board and continue to use it as a 3-channel receiver.  Since we don't do surround that is okay, but I'm not excited about having something that let out a poof of smoke running a few hours a day.

So I guess I'm taking the first option.

I hate that it's 50lbs of metal, much of it semi-rare copper, and it's going to end up in the trash.  It probably died because somewhere there is a 2 cent Chinese capacitor that failed.  This guy was built in 2002 when many products were made with these timebomb capacitors.  NAD (the manufacturer) doesn't have parts anymore, so I can't just replace the failed amplifier board.

Published 07 May 2008 03:34 AM by AlexWetmore

Comments

# Richard said on 06 May, 2008 08:56 PM

Have you considered taking it by one of the audio repair shops on Roosevelt?  Sadly, its probably cheaper to just replace it than repair it.

# AlexWetmore said on 07 May, 2008 06:14 AM

I have.  It is somewhat a matter of trust, I don't want to get it repaired then have another component in it die and go up in smoke.

It also looks pretty complicated to disassemble.  There is a huge heatsink in the middle with a lot bonded to it, including the part that died.

# Mike said on 07 May, 2008 06:48 AM

I really like reading about the tinkering you do.  I'm surprised you aren't listening to some home-made vacuum tubed equipment.  I've made some equipment from these guys http://www.bottlehead.com/ and it sounds great - and is easy to repair if needed.  

# Jimmy Livengood said on 07 May, 2008 11:47 AM

Ouch. There must be stereo geeks in the same vein of bike geeks who could do something about this, or at least help it avoid the landfill?

# Jon Cameron said on 07 May, 2008 12:29 PM

Hi Alex,

I'm in the Hi-Fi biz for more than 20 years now.......take this unit to a qualified electronics repair tech. Even if NAD is no longer supporting it with service, a quality tech has a reasonable chance of fixing it. ( After all, it is ONLY five years old ) Please don't lose faith in it over what might be a simple repair. You think nothing of rebuilding a wheel because these are skills that you possess. From reading your blog for awhile now, you seem like a pretty independent fellow. Don't let yourself be intimidated by one of the few things that you can't fix yourself. Accept some help on this one, and we might be able to keep it out of the landfill for another fifteen or twenty years. Thanx, Jon Cameron.

# Alex Yip said on 08 May, 2008 11:42 PM

Hi Alex, if it really is a capacitor, you might be able to find it just by looking around on the board.  I had a electrolytic cap blow on a monitor once.  It was pretty obvious.  The cap had a flat top with an X crossed on it, and the top was puffed out like a dome.  Replaced it 6 years ago, and the monitor is still running.  Another option is to sell it.  I'm sure someone would buy it on ebay.  Maybe for more than you expect.

# AlexWetmore said on 14 May, 2008 01:10 PM

Since this is the stereo that gets used in our house more than any other (probably 10x more than any other, and primarily by Christine) I did end up replacing it.  I bought a Marantz SR7002 that was on sale for a very good price.  It isn't quite as nice, but it's still pretty good.  I sold the dead receiver on craigslist.

Mike -- I do have some kits amps too.  Our kitchen and outdoor speakers are powered by a 41hz.com AMP9 (4 channel amp built around a tripath chip) and my office speakers are powered by a 41hz.com AMP6.  The kit amps are a lot of fun and the tripath chips are nice for this sort of use because they are very efficient and don't burn up power when there is no input signal.  For our living room though we really just need something 100% reliable and which works.