CARVER PM-1200 Amplifier excessive buzz

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CARVER PM-1200 Amplifier excessive buzz

Post by vyee » Tue May 19, 2009 10:40 am

My PM-1200 amplifier has a significant buzzing noise that is very distracting. After taking off the cover, I have concluded the hum is coming from the transformer. Any suggestions for at-home repair? Or should I merely leave it to the pros to serivice it?

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Re: CARVER PM-1200 Amplifier excessive buzz

Post by thuffman03 » Tue May 19, 2009 12:09 pm

Unless you are good with electronic repair I would send it off to Bob and Rita to have repaired.
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Re: CARVER PM-1200 Amplifier excessive buzz

Post by gary_wong5 » Wed May 20, 2009 7:26 am

My TFM-45's left side was always buzzing and very annoying. However, the buzzing noise disappear after I tried connecting a single wire from CD player<---->preamplifier. What a wonderful day. \:D/

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Re: CARVER PM-1200 Amplifier excessive buzz

Post by donberry » Sat May 23, 2009 10:06 pm

I could be way off base here so take this with a grain of salt, do not even know if this is your problem, but may be worth a shot.
Could it be a ground loop hum ? I had a really bad hum on a Crown DC-300A II amp I have and checking around about it, came across an article somewhere that recommended using a multi-strip, where it was just plugged straight into the wall.
Again, do not know if that is your problem, but it did work for me, went to a mult strip and the problem went away(when I say a multi strip, I am just talking about those power strips with multiple plugs on them, so you can plug 500 things into one outlet)

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Re: CARVER PM-1200 Amplifier excessive buzz

Post by BillD » Wed Jan 06, 2010 8:23 pm

Sometimes buzzing is because you are drawing too much current. Check you bias adjustment and rail voltages.
It should sound like it isn't there!
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Re: CARVER PM-1200 Amplifier excessive buzz

Post by birdyman » Wed Jan 13, 2010 10:24 am

Can you disconnect everything and see if you still hear hum? If you do your amp has problem. If disconnecting solves problem, you have ground loop. Ground loop can be from : not limited to, cable box, cable or dish TV, long line to projectors, long line to subwoofers...etc. You just need to reconnect one at a time to see culprit. Let us know what you find. I hope this help.

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