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BELL SYSTEM TECHNICAL JOURNAL 



List of Towns where Room Noise Survey Measurements were Made 



each source must be reproduced separately in its own position. On 

 account of binaural effects in hearing, the proper locating of sources 

 seems to have a considerable effect on naturalness. The most practi- 

 cal method of securing an approximation to this effect in the reproduced 

 noise is to dispose a number of loudspeakers in different places in the 

 room, chosen by test so that false directional effects are avoided. 

 Third, the effects of reverberation must be considered. A noise picked 

 up in a highly reverberant room, and reproduced in another highly re- 

 verberant room, w^ould have in it tw^o sets of reverberations. The best 

 method of taking care of this seems to be to make artificial adjustments 

 in the reverberation in the two rooms. Finally, there is a residual 

 effect due to the fact that a person experiencing an actual noise is aided 

 in his recognition of the noise by visual and other factors enabling him 

 to refer it easily to its source; these are, of course, not present when the 

 sound is reproduced. 



