I don't know what your tolerance would be...the way to check accurately is
to run a plot using an audio generator, sweeping from 20 Hz to 20k Hz and
taking an average...or merely using the plot like you see in speaker spec
sheets. Running a few of those compared to your 'quick & dirty' procedure
below will give you your tolerance. White (or pink) noise would be
preferable to 'normal' (just what is 'normal' anyway) program material, as
you will have a consistent measurement.

jak

"RWatson767" wrote in message
...
Mike
Can you measure Impedance with an Ohm Meter

Which begs another question: will playing normal audio material through a
speaker, and measuring the ac voltage and current match the nominal
impedence
reasonably well, say within 10%?

We used to measure voice coil and other audio impedance by inserting a low
ohm
resistor in series with the load. We did have an idea of the actual
impedance.
We onfirmed this by reading the voltage across the resistor. We also
checked
the procedure by using actual carbon resistors to "calibrate" the
procedure.
Bob AZ