If a "naked" microphone is hit by a stream of air, it breaks up against the hard edges of the inlet and creates air vortices. When the broadcast goes under the open sky, the wind is howling in the microphone. Therefore, a microphone is worn with a fur or foam cover - windshield, which breaks the air in front of the microphone. Covers are also needed in the studio, as some singers or speakers "spit" the air on explosive consonants - "P" or "B". Listeners get a "blow" to the ears. Thus, without wind protection, neither a quality live sound nor a professional sound recording is possible.The shielding material used – wire gauze, fabric or foam – is designed to have a significant acoustic impedance. The relatively low particle-velocity air pressure changes that constitute sound waves can pass through with minimal attenuation, but higher particle-velocity wind is impeded to a far greater extent. Increasing the thickness of the material improves wind attenuation but also begins to compromise high frequency audio content. This limits the practical size of simple foam screens. While foams and wire meshes can be partly or wholly self-supporting, soft fabrics and gauze require stretching on frames, or laminating with coarser structural elements

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