Calculated Loudness Comparison of Artificial Noises

A number of artificial stationary noises given by their spectra have been objectively evaluated with respect to loudness. The results of Zwicker's graphical procedure for free and diffuse sound fields are compared with the calculation methods according to Stevens and Niese based on third octave and octave data. In some cases there are considerable differences between the calculated loudness values. From parallels to practically existing noises the possibility is pointed out, of getting an approximative prediction of the loudness differences to be expected, when using the three different methods for loudness calculations.