GRAS AM0364 Windscreen for Array Microphones

Introduction

The AM0364 contains 6 spherical windscreens specially designed and optimized for use with 1/4" microphones in array configurations 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 by pushing it as far as possible over the microphone.

Design

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 size of AM0364 is choosen with consideration to reduce interaction between neighbor microphones in the array.

The GRAS windscreens are all size optimized for dedicated Array microphones and standard 1/4" microphone sets mounted in array modules GRAS PR0001 & PR0002. The 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.

Alternatives

If you need to make sound pressure measurements in a well-defined laminar airflow, e.g. in a wind-tunnel, we suggest that you look for GRASstandard microphones combined with nosecones. Alternatively look for our surface microphones or our new flush-mounted microphone concept which can also be arranged in an array configuration.

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 windscreens we offer a 6 month warranty.