Audibility of Spectral Dips and Peaks in Broadband Noise
* Presenting author
The paper reports on the ability of people to discriminate between sounds with slightly different frequency spectra. This is relevant in architectural acoustics, for people with a visual handicap who are navigating space by means of echolocation and acoustic recognition of spaces. This is done in room and building acoustics contexts respectively by interpreting just noticeable differences in colour of sound reflection from interior surfaces; and by judging sound transmission spectra, such as the relevance of subtle sound insulation deteriorations of improvements of walls. Stimuli were created by damping or amplifying a frequency band centred around 125Hz or 2kHz of broadband pink noise with varying bandwidth and reduction/enhancement factor. Perception tests involving 12 human subjects confirm expectations. On average spectral dips are more difficult to detect than peaks. No statistical significant difference was found in the performance of subjects at different presentation levels (Lp,A=35 or 50 dB).