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PostPosted: 11 Dec 2010, 16:07 
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Joined: 21 Dec 2009, 15:51
Posts: 31
:eek: I ran upstairs as soon as the house lights started to flicker to save and turn off pc as well as my Music Angel MA845 tube amp expecting a power cut.

PC saved, phew, off with the amp and the house lights stopped flickering and are now fine.
The amp was idle at the time but sounded fine minuets before.

What could be the problem?
FTI


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PostPosted: 11 Dec 2010, 18:49 
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Joined: 14 Feb 2010, 13:13
Posts: 663
Location: Lisbon, Portugal
Hi!

That is very odd and dangerous. Does the amplifier have mains fuse? Do you share your walls / illumination circuit??? What about earth? Are you using it?

For your safety, keep posting and do not turn the amplifier on again!

Miguel


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PostPosted: 11 Dec 2010, 21:48 
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Joined: 06 Jun 2008, 18:23
Posts: 5115
Location: Australia
You should always fuse the AC - slow blow fuse. And earth the top plate of the amp to stop it going live.
Further fusing can be placed after the rectifies - fast blow here.

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Projects:"retro2308" - chip based headphone amp | ”Calibre 834” - tube phono MM preamp | ”najah” - Raw 180W Tripath Class D power amp | "Icon" - Shuguang CV-181Z preamp


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PostPosted: 12 Dec 2010, 02:17 
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Joined: 05 Jan 2010, 21:16
Posts: 680
Location: Las Vegas Nevada USA
freetradeinn wrote:
:eek: I ran upstairs as soon as the house lights started to flicker to save and turn off pc as well as my Music Angel MA845 tube amp expecting a power cut.

PC saved, phew, off with the amp and the house lights stopped flickering and are now fine.
The amp was idle at the time but sounded fine minuets before.

What could be the problem?
FTI

If the the amp drew enough current to flicker the lights for that length of time I would expect some sort of burning or arcing smell to accompany this situation. If you smelled nothing you probably have faulty house wiring and a loose connection somewhere and it had nothing to do with the amp, although the idle current of the amp could cause the problem to show up.

Get a "3 Light outlet tester". It will show if your outlets are correctly wired in the first place, and a flickering light, especially while "jiggling plugs" in connected outlets, can help diagnose loose connections.

I agree with the above though. Don't plug the amp back in to the wall unless you either find the problem and correct it or the amp is isolated from persons and property and you're taking safety precautions. If you don't know how to work on ams don't open it.

Strange problem. I'm betting something is loose and it wasn't a short (the smell factor :wizard: ).

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PostPosted: 12 Dec 2010, 20:43 
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Joined: 24 Nov 2010, 14:39
Posts: 32
Location: California
As an electrician, I'd probably tend to agree with the "bad / loose connection" scenario, especially if the flickering was affecting the entire house. Where are you located? Wiring methods vary from country to country. I've seen this type of whole-house situation when there is loose / bad connections in the main circuit breaker (or fuse) box (dangerous situation). Has it reoccured since that initial episode, without your amp plugged in?


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PostPosted: 13 Dec 2010, 10:36 
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Joined: 21 Dec 2009, 15:51
Posts: 31
First cheers for the comments.
I have been informed that there was significant power problems in my area with houses losing power altogether.
I am no longer experiencing house wide strobe and the amp is back on ok.
As a precaution I am using it with the house lights on as a warning for trouble just in case it wasnt a coincidence.
EDIT- Also the amp sounds awesome and I have been told that I will hear problems before things actually self destruct.

FTI


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PostPosted: 13 Dec 2010, 12:05 
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Joined: 14 Feb 2010, 13:13
Posts: 663
Location: Lisbon, Portugal
freetradeinn wrote:
I have been informed that there was significant power problems in my area with houses losing power altogether.

:shock: :shock: :shock: Was this due to your amplifier?!?!? :mrgreen:


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PostPosted: 13 Dec 2010, 13:14 
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Joined: 24 Nov 2010, 14:39
Posts: 32
Location: California
FTI,
Great - glad to hear it for a couple of reasons:

1. Someone else had to fix it and it didn't cost you anything, save for some worry.

2. If there was a bad connection in your home, it would almost certainly be at a wall outlet that is located behind the largest, heaviest piece of furniture that you own :D

Best Regards,
Jim


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