Hey Bill, my designs have been measured with HolmImpulse, but with varying voltages, mic distances, gating, outdoors/indoors, etc. Wouldn't that matter? And doesn't the measurement setting have to be very quite. I usually go outdoors. Maybe I'll pull up some of my old measurements and take a look, but usually I ignore distortion based on the randomness of measurement processes. Usually high sensitivity designs are really low distortion anyways.