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PA amp + speakers

Hello, I have a small carlsbro pa + speakers. The problem is - all i'm getting from the rear speaker outputs (4 ohms min) is constant white noise?

I have checked the speakers with a different amp, they are fine. Plus I have tried the mono output on the front panel, this works too.

The noise happens even when all the volume dials, includind the main volume are turned to 0. I have also tried different cables, no success.

 I notice when I turn off the power switch, as the power fades I can hear my mp3 player working for a split second.

I have just opened it up and all the soldering looks good.

Any suggestions

regards Matt



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Re: PA amp + speakers

Well I do not know what your knowlage of amps is but take an ohm meter and check all your Cap's that sit on the output stage of your Power Ic's. The noice your are getting is ripple from the AC side. When you switch of the amp there is no power and no ripple so all you here is the correct DC power that is going thru to your Power Ic's. that power is supplied by the Cap's that is busy discharging. You will find your problem there.

Posted on Jun 02, 2008

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Re: PA amp + speakers

Remove every sound input one by one until you find the one who make the trouble.if this procedure failed sent it to sevice center to fix it.

Posted on Mar 11, 2008

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