This paper discusses comparisons made between two ground-based outdoor microphone configurations. The first consists of an inverted microphone placed above a convex circular plate and covered by a large dome windscreen. The second, updated, configuration is similar but has a thicker windscreen and a thinner ground plate. Both were subjected to laboratory testing where their responses to sound were recorded at several different elevation and azimuthal angles. At almost all shown elevation angles, both configurations recorded levels that were within ±3 dB of a baseline measurement between 50 Hz – 20 kHz. At all shown azimuthal angles and over the same frequency range, both configurations recorded levels within ±2 dB of the levels reported at an azimuthal angle of 0°, with the updated configuration having less variation. Both were also subjected to wind noise testing, where the updated configuration demonstrated superior wind noise rejection at low frequencies. The conclusion is that both are suitable for outdoor acoustical measurements and that the updated configuration is superior, especially when measuring low-frequency noise.

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