Friday 24th November 2023 12:00 – 13:00. This seminar will be a hybrid event, with online access via the Teams Link.
Acoustical measurements commence with microphones. For the convenient frequency range of 20 Hz to 20 kHz, and within the level span of 30 dB to 130 dB, it is typically straightforward to select an appropriate microphone. Beyond these ranges, it is often necessary to develop specialised microphones tailored to the specific task at hand. This could entail measuring extremely high sound pressure levels in proximity to a jet engine operating in afterburner mode or detecting drone noise registering below 0 dB at substantial distances (it’s worth noting that 0 dB doesn’t denote no noise but rather the lower limit of human auditory perception). Alternatively, these specialised microphones might be designed for precise measurements of sonic booms at low frequencies, hovering around 0.1 Hz. At the other end of the frequency spectrum, high-definition impulse measurements may necessitate broad frequency coverage extending up to 200 kHz, where considerations related to size and dynamic range pose challenges.
This presentation will explore various measurement scenarios and delve into the design considerations and challenges we have successfully addressed over more than 30 years of collaborative work with researchers and engineers from universities and companies worldwide.
Per Rasmussen M.Sc. and Founder of GRAS has more than 40 years of experience in the design and application of measurement microphones for a wide variety of industries including automotive, aerospace and consumer electronics. This includes applications ranging from measurements on cars, aircrafts, drones, impulsive noise sources, wind tunnel measurements, headphones etc.