Helmoltz resonator used in compact, portable meter measures acoustic impedance of ground or other surfaces. Earth's surface is subject of increasing acoustical investigations because of its importance in aircraft noise prediction and measurment. Meter offers several advantages. Is compact and portable and set up at any test site, irrespective of landscape features, weather or other environmental condition.
Acoustic Ground-Impedance Meter
NASA Tech Briefs ; 7 , 2
01.05.1983
Sonstige
Keine Angabe
Englisch
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