Quote Originally Posted by valhallax View Post
with the woofer tester one places the woofer in a stand and it measures the parameters.
But the measurement has to be taken SOMEWHERE, ie at some distance from the cone. If you measure a foot from the cone, you will need to knock off 4.5 dB or so. Otherwise you can not communicate with others, and your box designs simulation will be off. TS parameters efficiency is at one watt/one metre, and all box design programs I know of use that standard.

Doesn't the woofer tester just calculate by using a comparison sweep? It doesn't measure efficiency as far as I know. It makes an educated guess.