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    How to measure impedance amp is seeing from sub with DMM

    The title says it all. Is there a way to do this? I have a True RMS multimeter on hand







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    Re: How to measure impedance amp is seeing from sub with DMM

    This is stickied in the Help 101 tab at the top of the forum. You know Ohm's Law?



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    Re: How to measure impedance amp is seeing from sub with DMM

    No not while it's playing... you can measure DCR of the subs. Unless you're burping there is no reason to find out because impedance curve will be different based on the frequency being played.



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    Re: How to measure impedance amp is seeing from sub with DMM

    Just put ur dmm to the sub n get an idea of "baseline" resistance




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    Re: How to measure impedance amp is seeing from sub with DMM

    Quote Originally Posted by neo_styles View Post
    This is stickied in the Help 101 tab at the top of the forum. You know Ohm's Law?
    Ok i will check that out. Thanks!




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    Re: How to measure impedance amp is seeing from sub with DMM

    Just measuring the impedance of the speaker will usually give you a good idea.

    Are you wanting to know worst case scenario? Sometimes for fun I will use Winisd (LinearTeam) to model the speaker and box that I have. I take the lowest point in the models impedance curve and play that frequency through my system while clamping (https://www.youtube.com/watch?v=oTvE9KyQstg) the amplifier. With this result you can calculate out the lowest actual impedance your amp should see at any frequency.




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    Re: How to measure impedance amp is seeing from sub with DMM

    measuring impedance curves is what the DATS or WT-3 is for.

    Dayton Audio DATS Dayton Audio Test System 390-806

    using Ohms law to measure impedance requires you know two of the four parameters + know what frequency you are playing. Voltage is easy and a given. Current is the next option, and fine for low volume testing.



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