trouble shooting speaker crossover board

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Hi
I bought a second hand pair of speakers (OK that was dumb)
They are denon passive speakers. One speaker works the other one does'nt. On the speaker that is not working I have swapped the driver units into the working speaker and they work fine. Therefore I am assuming that the problem lies somewere on the crossover board ( I have already substituted speaker cables and the amplifier -speaker output connections).
I am very new to electronics so am not sure how to proceed now. My cross over board has 2 capacitors a small coil of wire, 2 components which have written on them 5W 2.2 ohms JF, and another item which is shrink wrapped in blue plastic and is the size of a small battery.
Would be grateful if anyone could suggest were I could go from here.
Incidentally as I had nothing better to do I measured the current and voltage of the wires from this board when attched to the amplifier and these gave similar currents and voltages to those on the working speaker. I have tried checking the capacitance of the two capacitors but am not sure if I am doing it properly as I have just got a new meter and sometimes the capacitance is within limits and other times I get a reading saying OL?
 
Well you seem to be doing OK so far.

The coil is basically 100% reliable, so not a problem.

The 2.2R 5watt resistor is easy to check with your multimeter.

Which leaves the 2 presumably bipolar electrolytic capacitors,
a failure of one is unlikely to give a completely "dead" speaker.

And your unknown component which could be for power
protection purposes.

Carry on the way you are going, get out your soldering iron
and swap components one by one till you find the culprit.

If the unknown component measures short in one speaker
that works and open in the other it is probably the culprit.

Could also be a dry joint on the crossover board.

:) sreten.
 
Hehehe, now it appears that buying those speaker could have beens a good idea. Hope you didn't pay for the price of a new component :)

BTW, you can let us know your Denon type (or a picture), just who knows.

Looking from the components, the 5W 2.2Ohm things are the L-PAD, and the others are components for 2nd order filter. In other words, the blue thing could be just a transformer, or a coil with steal lead inside of it (The speaker may need more than just a "small" coil)
 
Just a short note to let you know that I have solved the problem. It was quite interesting as I tested all of the components on the crossover board and found their values to be as expected. It appeared that the problem was caused by a small piece of black plastic which was trapped between the negative lead inpoint and the crossover board thus preventing a contact between the board and the lead connector. The speaker is now working fine, thanks for your help Sreten and Jay.

regards
Michael
 
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