An industry friend and I were talking about the importance of having matched measurement mics and he mentioned this lab:
QUOTE:
MACH™ Testing
Multi Angle Computerized High-speed Testing™
Originally developed by NASA scientist, Ron Sauro, in 1968 for use in testing the Pioneer, Explorer and Voyager spacecrafts in addition to the mannned Apollo lunar program, the MACH™ Testing method has been reformulated into a revolutionary process for evaluating loudspeakers and materials. This cross-pollination of technology from the realm of space research to the world of sound and acoustics research has produced a high-speed testing system unlike any other.
The MACH™ testing method uses a proprietary array comprised of 19 matched Earthworks M-30 microphones, three custom modified Presonus microphone preamps and a Linear X precision turntable capable of one tenth degree accuracy during the rotation of the device under test. It simultaneously samples impulse responses within an extremely large, free field environment and uses these to create loudspeaker directivity balloons in a fraction of the time used by other testing methods. This data is gathered by a multi-channel version of EASERA, using appropriate stimuli, and then is converted to EASE V4, EASE V3, and CLF 1 and 2 formats for transmission to the client. EASE GLL formatting is also available for an additional charge.
END QUOTE:
Seems like a field trip is in order…