The AM0378 is a windscreen specially designed and optimized for use with GRAS 41AC Outdoor microphones for sound pressure measurements under free-field conditions, e.g. in situations where the wind comes from more and unpredictable directions. The windscreen is mounted over the top cone of the microphone. See the manual for the Outdoor microphone for instructions.
When a microphone is placed in a laminar flow, turbulence is created which in turn results in unwanted pressure variations on the diaphragm. By using a windscreen the pressure variations are moved as far away from the diaphragm as possible.
Theoretically this supports a “the-bigger-the-better design”, but in practice it is a compromise between air speed reduction, practical size and self-induced noise. Self-induced noise is wobble-noise which is generated, when the windscreen starts moving around the microphone.
The GRAS windscreens are all size optimized and their special, open-cell foam structure and number of pores per inch2 (ppi), are designed to resist a humid environment and at the same time not influence the sound pressure measurement result significantly.
Frequency dependent attenuation is to be expected if the windscreen gets wet. Therefore windscreens are not intended as rain protection of the microphone.
The windscreen is easily removed during calibration of the microphone.
Quality & Warranty
GRAS accessories are made of stainless steel, alloys and high-quality composites. These items are covered by a 2 year warranty respecting their intended use.
On consumables like batteries, cables and windscreen we offer a 6 month warranty.