How much can be measured -- and how much cannot?

Unsound, you are right, speaker frequency response and sensitivity matter. All the cases I was alluding to were electronic components.

Tbg, how about an amplifier's dBW into impedance? Or the predictable roll off at frequency extremes when there's issues of impedance mismatch or capacitance issues? Antenna and tuner specs can often tell some how well they can receive certain stations at a given locations. Those are just a few examples.

Sabai, what do you mean by the phrase "the essence of music" and is it related to high end audio?

Tbg, What that tells you is that M Fremer is either not sensitive to the results of the 'bad measurement', that his equipment isn't sensitive enough to reveal the result of the bad measurement, or as often, that the 'bad measurement' is insignificant in real world conditions.

Unsound's comments about FM tuner spec's are correct, but as always with measurements those specs alone tell you nothing about how the unit will sound beyond its ability to pick up a clean signal. Yet a lot of folks can't tell the difference between the various tuners actual sound and buy them based on these spec's. It's curious that in a famous FM tuner site which has published a lot of reviews and has ranked tuners this is more true than anywhere. Very few of the reviewers are actually audio freaks, they a radio freaks, yet folks talk about the review rankings as if it were gospel.

FWIW to make measurements meaningful you must know in real life what they mean and how you can use the information productively. Just seeing and comparing spec's is a meaningless activity - often the most meaningful spec's, especially from manufacturers, is missing. Impedance curves for speakers and amps for example, which are very important, are hardly ever seen except in reviews by folks like Atkinson. Although I do recall one speaker manufacturer who did, but if you saw the curve you would know why - dammed near flat gentle curve between 5 and 8 ohms with nominal 6ohm rating. Just as with spec's, reviews are for the most part useless unless you have a good handle on the reviewers preferences and competence.

Bottom line, knowledge is great but hard to come by and even when possessed it isn't worth a crap if you don't know how to use it. :-) Sooner or later, if you last long enough, you will identify the spec's that will be meaningful to you and those you can safely ignore (most of the time).

Newbee, I couldn't agree more.