Assessment of annoyance, loudness and unpleasantness with different recording and playback techniques

The present study was carried out to investigate if there is a difference in perception of annoyance, loudness and unpleasantness between monophonic recordings played back through a loudspeaker and binaural recordings played back via headphones, and to evaluate whether a possible difference depends on temporal and frequency characteristics as well as spatial characteristics of the sounds. Evaluations were also done in order to see a possible effect of durations of sound exposures. The experiment adopted three psychometric methods for achieving responses from subjects. Fifty-four young students participated and three types of sounds were used in the experiments: everyday "restaurant" sound (from using cutlery at platters, moving chairs, talking etc.), road traffic sound and a low-frequency ventilation sound. The sounds were recorded with two different techniques (monophonic and binaural). The monophonic recordings were presented through a loudspeaker and the binaural recordings were presented through both closed (circum-aural) and completely open (free-of­ the-ear) headphones. Each sound was played back at three different levels. The results show that for all judgments (annoyance, loudness and unpleasantness), there was no significant main effect of recording and playback techniques; however significant interactions between techniques and sounds were found. For annoyance and unpleasantness, an influence of psychoacoustic method was found.