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Old 6th April 2012, 04:29 PM   #1
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Default Pass Aleph 2 clone alarm this fine AM

OK, I'm not going to cry, yet. I'm a huge fan of audio, but know very little about it's secret workings. I hooked up my Aleph 2 clone a few minutes ago and powered it up with the speaker cable connected, but without the RCA inputs plugged in. After about 10 seconds, I could see faint smoke coming out of the top vents. After a few minutes to let it cool down ( I didn't feel any heat but in case resistors were overheated) I played some music through it and it seemed fine. Did I likely damage anything? I hadn't used this amp in abut 9 months., if that's worth anything.
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Old 6th April 2012, 04:33 PM   #2
Zen Mod is offline Zen Mod  Serbia
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pictures please
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Old 6th April 2012, 07:00 PM   #3
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Did you see smoke or did you see and smell smoke? Sure you didn't imagine it?? Did you hear anything when turning it on? Maybe a pop inside the amp or at the speakers?

If you have a volt meter, check the output DC by setting the meter to a low DC setting and see if there is any DC across the outputs. Write down what you see. Don't hook up speakers until you figure this out. If you have a disposable pair of 8 ohm speakers, then maybe use them to test after fixing the amp.

Is it possible to pop an output mosfet, yet still have a running amp?
Aleph 2 has banks of mosfets. If one went, then the rest could be sharing the current. If you let it run, is one heat sink noticably hotter than the other?

I'm no expert electronics toubleshooter, but just trying to get the ball roling for you.


good luck!
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Old 6th April 2012, 11:02 PM   #4
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The smoke was faint white and smelled a bit. I called a tech friend who told me I was very lucky the whole amp didn't blow. He said something about a capacitor in the circuit whose purpose is to prevent damage through oscillation when inputs aren't hooked up, and that I should get a flashlight and look for any burned caps near the rear of the amp...then I'll run it again this evening and see if the output transistors all get hot.
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Old 8th April 2012, 04:02 AM   #5
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pictures please
This site isn't accepting my pics tonight?!
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Old 8th April 2012, 04:11 AM   #6
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Maybe you shorted the outputs and caught it in time?
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Old 8th April 2012, 04:25 AM   #7
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I ran it a couple of hours last night and it seems fine.
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Old 8th April 2012, 08:15 AM   #8
Zen Mod is offline Zen Mod  Serbia
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you know what ?

bring it back to Tim Rawson

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Old 8th April 2012, 08:30 AM   #9
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you know what ?

bring it back to Tim Rawson

What's that supposed to mean?
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Old 8th April 2012, 08:43 AM   #10
Zen Mod is offline Zen Mod  Serbia
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that means that you have potential torch in the house , according to all pictures of Tim Rawson's work

you weren't aware of that , prior to giving him money ?
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