Since its establishment in 1994, GRAS has been totally dedicated to the development and manufacture of high-quality measurement microphones and related acoustic equipment. It was founded by the Danish acoustics pioneer, Gunnar Rasmussen, who has been a major contributor to the world of sound and vibration with his unique ideas and designs. From the first reproducible 1” condenser measurement microphone that enabled quality measurements and instrumentation for acoustic calibration, Gunnar’s ingenuity and foresight led to the world’s most popular acoustic sensor: the ½” measurement microphone. The ¼” and 1/8” microphones followed with outstanding dynamic and high-frequency capability that brought higher definition and transparency into impulse noise diagnostics. Many variants have been made available for the years; all based on Gunnar’s original 1” pressure microphone design.