San Francisco : Architect and Engineer, Inc · leaf 416
her covered cases. One case contains a noisemotor, the second, the noise analyzer, and thethird, a microphone and batteries. The noise analyzer is not nearly as well knownas the noise motor which measures only the totalnoise or loudness. The noise meter gives noiseratings of boiler factories,… … Thirty-six passenger twin coach used for noise analysis.
Architecture · Building
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