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No-one ever told me to be wary if test speaker voice-coil continuity with a DVM. Speaker o/c in the amp cab, but after process of removing showed proper ohmage. Exposed pigtails looked ok and tested ok, so heated up and removed the dome. Made wire-taps to both voice-coil lead outs and tested each pigtail in turn. Both had the same break at about the same point of slowly manually pushing the cone in and out, so assumed I was deflecting the cone slightly. Very unlikely the same paint-covered failure at the joins of pigtails to wires , or anywhere else, so what was I doing wrong?

Answers here please

Reply to
N_Cook
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a
d
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From the west side of the pond.

What is o/c in the amp cab? The break could be at the wire junctions in the soldering process introduced some contamination/corrosive material. You don't say how old the speaker was, but any corrosion combined with the repetitive motion could vause a weak spot, THen if the volume was high, there could be local heating further aiding the process of failure.

Reply to
hrhofmann

a
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No breaks in the internal wiring. With using DVM and pushing the cone, generated enough voltage to fool the continuity mode into not bleeping. Intermittant fault was actually at the outside tag terminal inside the solder, pigtail corrosion/fatigue but held in place and disquised by the overlaying lacquer.

Reply to
N_Cook

In my experience the first fail spot due to fatigue is the braid of the pigtail where it's soldered to the connector tag, it's difficult to spot. Next place is on the inside of the cone where the tail of the voice coil is soldered to the pigtail. this is presuming that the speaker isn't being overdriven or the v/c isnt rubbing in the gap.

Ron(UK)

Reply to
Ron

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