It's a Ruby Amp Meltdown!!!

[additional gravy]

I had a ruby amp meltdown!!   

For one of my beginner projects I built the ruby amp as described on JD sleeps site http://www.generalguitargadgets.com/content/view/61/26/  Best to figure this one out before I move on to bigger things!

It sounded great and worked perfectly when i powered it with my 9 volt battery.  Then I unplugged my battery and tried the dc jack with an adjustable voltage  wall wart (1000mA max) set at 9v.  The LED did not light up and I heard a tiny "pop" and then the nasty burnt electrical smell (this took about 3 seconds then i quickly unplugged the wall wart).  I plugged my 9v battery back in and then the amp sounded like a farty poppy oscillating octavefuzz.  actually really cool sounding or shitty depending on your point of view.  i removed the LM386N-1 IC (radio shack http://www.radioshack.com/product/index.jsp?productId=2062598) and popped in a new one, now the Ruby amp works fine again (w/ battery only)  I checked and re-checked my wiring, circuits and can't figure out what's wrong!

Thanks for your time DIYers

Here is a little sprout of a blog with a picture of the wiring:  http://additionalgravy.blogspot.com/

[StereoKills]

Question: was the power adapter center negative or positive? and which was the Ruby set up to run on? That's my guess.

[additional gravy]

Yep, That's all it was. It works fine thanks!!!   The wall wart i'm using is one that has multiple tips of various sizes that plug into a tiny socket (no polarity switch) i plugged the "tip" to positive...so, wrong polarity.

[darron]

Sounds like a cool recipe for a unique distortion! Something to try one day... Save the IC lol.

[additional gravy]

yeah, i did!  i'm going to make an extra box and call it the "elephantitis" or something goofy like that   

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I blew an electrolytic cap on a ruby the exact same way. Luckily the amp enclosure was closed up at the time. But when I opened it up, a nice puff of smoke came out