Re: How to test speaker resistance

 

At 22-03-18, you wrote:
An ohmmeter isn't the proper tool. That's because what you want to know is the speaker impedance at audio frequencies, not its DC resistance. They are not the same thing.

You might get a reasonable estimate by using a true RMS voltmeter and an audio signal generator. Connect the signal generator to the speaker through a small series resistor, say 10 ohms. At several frequencies, measure the current into the speaker by measuring the voltage drop across that resistor, and measure the voltage directly across the speaker. The impedance at that frequency is then the ratio V/I. Do this at several frequencies across the audio range, since the impedance of the speaker likely varies a lot over that range. The average of the impedance measurements at all frequencies will give you an idea of the speaker impedance.

--
Art Greenberg
WA2LLN
art@...

On Thu, Mar 22, 2018, at 08:25, Dgyuro via Groups.Io wrote:
An ohm meter across the terminals is what it is 8 ohm, 4 ohm etc.
On Mar 21, 2018, at 3:25 AM, David Wilcox via Groups.Io <Djwilcox01=yahoo.com@groups.io> wrote:

OK. I am seeing various resistances listed for speakers. How would I test one? An ohm meter should indicate a short across the coil I would think. Please help.

Dave K8WPE

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