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Amp cutting out... why?

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zimble01
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Hello everyone.

I am experiencing a strange problem with my pair of Wharfedale 9.4s. If the volume of my RA-04 is turned past 8 o'clock, the amp cuts out. This never used to happen (in fact this morning it was still working). I have determined that the problem is with the right-hand speaker - if one unplugs the right-hand speaker and runs the amp through the left one alone, everything is fine. I have also tested the speakers with another old amplifier, only to experience the same problem with the right-hand speaker.

Further experimentation showed that if I removed the gold/copper plates that join the LF driver and the tweeter at the binding posts, and ran the speaker through only one of its drivers, then the amp did not cut out. I experimented with replacing the plates with some speaker cable - same problem. Finally, I opened the speakers (simple hex screws keep the LF driver in place) to find no shorting wires or loose connections, even at the crossover.

Many thanks in advance for any suggestions. 

zimble01
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Re: Amp cutting out... why?

 Anyone? Help would be greatly appreciated.

Andrew Everard
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Re: Amp cutting out... why?

 So when you remove the jumpers on the speaker terminals, which driver is still working?

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zimble01
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Re: Amp cutting out... why?

 Hi Andrew.

When the jumpers are removed, and the amplifier's
signal is sent through the whole left speaker and ONE of the right-hand
speaker's drivers (either tweeter or mid/bass), the amp doesn't cut
out.  However, when I run both speakers in their entirety, as they
should be run, then the amp will cut out. If the right-hand
speaker is run on its own, from either the left or the right amplifier
outputs, it causes the cut-out also. I have conclusively proved that
neither the cable (by some freak of nature), or its banana-plugs, are
at fault.

Many thanks.

zimble01
 

 

Andrew Everard
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Re: Amp cutting out... why?

 Then definitely the fault is in the right hand speaker crossover.

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zimble01
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Re: Amp cutting out... why?

Problem fixed!

When in doubt, never dismiss the option of a little handywork... 

Andrew Everard
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Re: Amp cutting out... why?

 And the solution was...?

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