Experimental Investigation in the Anechoic Chamber on the Loudness of Acoustic Noise Caused by A.C. Corona

The paper reports on an experimental investigation in the anechoic chamber on the physiological effects of the acoustic noise caused by a.c. corona. The first part of the investigation includes a comparison of loudness of a few corona noises having different frequency spectra anid, in particular, different levels of the 100 Hz component. On the basis of the results obtained, conclusions are drawn on the most suitable weighting methods for the corona noise and possible corrections to the usual A-weighting method are suggested. The second part of the investigation considers the problem of the scale of loudness for the corona noise (variation of the loudness with the sound pressure level of the noise) and includes also a comparison of loudness of the corona noise with other types of noises. The results obtained may be useful in defining rational criteria for the choice of the acceptable levels of corona noise.