Crossover Issue

intangible
intangible Posts: 262
edited January 2011 in DIY, Mods & Tweaks
I bought a pair of Monitor 10 Series 2, and one of the crossovers had a burned up resistor, so I decided I would go ahead and recap them while I had one out anyway. After doing the first one, the tweeter works, but I get no sound from the woofers. Based on the schematic, the only item in series with the woofers is inductor L2, so I resoldered the lead I had to cut to get the board out of the speaker, but the problem persists. Any ideas as to what else to try or instructions on how to test one of these with a multimeter?
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Comments

  • w_coyote
    w_coyote Posts: 66
    edited January 2011
    I would pull the other crossover and compare the two just to make sure everything is where it should be. If everything is correct then I would start checking all my connections. After that -not sure.
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  • Outfitter03
    Outfitter03 Posts: 563
    edited January 2011
    If you have a multimeter, you can do a continuity test (resistance) along the signal path quite rapidly. I would just disconnect the connections to the drivers and start by checking binding post positive (source) to speaker connector + and then speaker connector - to negative binding post.

    If you find a high reading in either leg of the test, narrow it down to the component or solder joint by half splitting. Pick a point somewhere in the middle of the fault leg and test each way. This should lead you to your open.
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  • intangible
    intangible Posts: 262
    edited January 2011
    Alright, after poking around, it looks like I got a bad cap. I suppose the lesson here is to check your parts before soldering them in. Thanks for the help.
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  • Outfitter03
    Outfitter03 Posts: 563
    edited January 2011
    How did you decide that the cap was bad?
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  • intangible
    intangible Posts: 262
    edited January 2011
    The multimeter can't put a voltage across it, whereas with the other caps I've got it can.
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  • intangible
    intangible Posts: 262
    edited January 2011
    Alright, I fixed my issue and figured I would put the answer here for posterity. I pulled the cap out, and it was fine. For reasons that would probably be obvious if I knew more about circuits, that cap (C1) took much longer to charge than the others. The issue was inductor L2, as I originally thought. It's leads, except for the part that I clipped to get the crossover out, are covered in a non-conducting film that has to be scraped off before you solder them back down. I assume this is to keep the coils from interacting with each other, but I didn't think about it, because when I moved an inductor redoing my 2B's crossovers I desoldered it directly rather than clipping it first. Pretty obvious in hindsight. Thanks again for the help.
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  • Outfitter03
    Outfitter03 Posts: 563
    edited January 2011
    Glad to hear you got it solved. Let us know how they sound once your caps have broken in a bit.
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