Speaker's efficiency, sensitivity and impedance


Hi folks, this has been discussed earlier but could you please explain once more in a rather simple manner what the relation is between a speaker's efficiency, sensitivity and it's impedance? Does a low impedance loudspeaker also have low efficiency? In reversal: does a low efficiency speaker have low sensitivity and low impedance? Thank you in advance.

Chris
dazzdax
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Tvad- Read Robert Harley's "Complete Guide to High End Audio" available from Amazon=8>) The sections on "How Much Power Do I Need?" and "The dBW Power Rating" may lend some clarity. The only aspect Mr Harley leaves out is converting volts to dBW.(pages 159 through 162 in the Third Edition) I had skipped over the part you sited, and concentrated on the section right after when reading the Transcendent article. The writer forgot to say, "Trust me!"
Audiokinesis Duke, Thank you for the first complete explanation of this commonly misleading conundrum, I’ve heard..

Happy Listening!
Is it safe to conclude that the impedance of a speaker gives an indication of the current demand on the amp? It seems that as impedance falls there would be more current drawn to keep the equation in balance. If the amp is not able to supply the current we get clipping.
Is it safe to conclude that the impedance of a speaker gives an indication of the current demand on the amp
That would be very safe! That IS what the impedance actually tells you. It just doesn't tell you the whole story -- but it's a good part of the story!