A test for amp polarity? Try this!

Discussion in 'Amps and Cabs' started by Tone_Terrific, Dec 20, 2009.

  1. Tone_Terrific

    Tone_Terrific Member

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    From time to time the proposition is put forward such that the speaker should move forward with a positive input pulse to the amp.

    The test, unless I have missed something, (and THAT sure can happen) has been to make a speaker cable polarity reverser, of some sort, and try both ways, pick the preferred configuration and enjoy the max in sonic response.

    It dawned on me that the old pickup polarity test, using a meter and bringing a metal rod (screwdriver, here) in contact with a pole piece generates a viewable/measurable pulse.

    Soooo....whack your pups with some metal and watch or feel the speakers hop. This seems to work.:banana You may want to verify that your pup is wired to respond positively to the contact.

    Stiff cones take a good bit of power to pulse visibly. It's quick.

    Once you master the method, checking the whole signal chain, pedals and all, for signal inversion, should be possible. I haven't done that, yet.

    Fitting reversed speaker cables to cabs, once you have determined your amp's polarity, may become necessary.

    All amps are not the same, so you may need to fit or provide 2 separate cables and use according to the amp's needs as you swap cabs.
     
    Last edited: Dec 20, 2009
  2. Tone_Terrific

    Tone_Terrific Member

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    This was a hot topic a while back.
    Kimock loves this stuff.:D
     
  3. Tone_Terrific

    Tone_Terrific Member

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    I think this is a valid tip.
    Seems a bit strange that there are no comments on its accuracy or merit.:dunno
     
  4. StratTone

    StratTone Member

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    Never heard of this one but I'm listening. ;)
     
  5. hasserl

    hasserl Member

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    Careful, sending shock waves thru a permanent magnet is a good way to destroy the magnetism. I think you could end up ruining the magnets in your pickups doing this.
     
  6. Tone_Terrific

    Tone_Terrific Member

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    Interesting thought.
    It only takes a few clicks on one pole to establish the effect. I hope magnets are more rugged than that.
    Tape over the end of the screwdriver would prevent direct contact, if that is what would most stress the mags.
     

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