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<blockquote data-quote="Ge0" data-source="post: 3513398" data-attributes="member: 582277">Hello all,Brand spanking new to this forum.&nbsp; Although, I have been active in others for over 10 years.&nbsp; I hope to pop in here once in a while and learn a little / contribute a little.&nbsp; Some of you may know me from rec.car.audio, ECA, or DIYMA.IgnoreMe,I see others have baffled you with techno-lingo that even they themselves may not fully understand.&nbsp; Hell, I&#039;ve designed electronics for 15 years and still do not grasp the entire electro-mechanics of a simple fuggin loudspeaker.To make it simple.&nbsp; A conventional DMM measures resistance by sending a known current through a resistive load and measures the voltage drop across it.&nbsp; Ohms law states V=IxR.&nbsp; You can re-arrange this to read R=V/I.&nbsp; So, if you know current, and can measure voltage, you can calculate resistance.Now, a loudspeaker is a transducer.&nbsp; In case of a loudspeaker, this means that if you supply a current to it, it will move.&nbsp; On the contrary, if you move it, you will induce a current.Now think about that DMM forcing a current through the voice coil to take a resistance measurement.&nbsp; Push on the cone and you&#039;ll induce a current that will either add or subtract from the current being injected buy the meter.&nbsp; The meter knows no different and calculates resistance based on whatever it sees.&nbsp; In this instance, by pushing the coil you are corrupting its reading.That is why you see the resistance measurement change when you monkey with the speaker.Is this good enough?Ge0</blockquote>

[QUOTE="Ge0, post: 3513398, member: 582277"] Hello all, Brand spanking new to this forum. Although, I have been active in others for over 10 years. I hope to pop in here once in a while and learn a little / contribute a little. Some of you may know me from rec.car.audio, ECA, or DIYMA. IgnoreMe, I see others have baffled you with techno-lingo that even they themselves may not fully understand. Hell, I've designed electronics for 15 years and still do not grasp the entire electro-mechanics of a simple fuggin loudspeaker. To make it simple. A conventional DMM measures resistance by sending a known current through a resistive load and measures the voltage drop across it. Ohms law states V=IxR. You can re-arrange this to read R=V/I. So, if you know current, and can measure voltage, you can calculate resistance. Now, a loudspeaker is a transducer. In case of a loudspeaker, this means that if you supply a current to it, it will move. On the contrary, if you move it, you will induce a current. Now think about that DMM forcing a current through the voice coil to take a resistance measurement. Push on the cone and you'll induce a current that will either add or subtract from the current being injected buy the meter. The meter knows no different and calculates resistance based on whatever it sees. In this instance, by pushing the coil you are corrupting its reading. That is why you see the resistance measurement change when you monkey with the speaker. Is this good enough? Ge0 [/QUOTE]

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