Dynamic compression and sound quality of music

Amplitude compression is often used to match the dynamic: range of music to a particular playback situation in order to ensure, e .g ., continuous audibility in a noisy environment or unobtrusiveness if the music is intended as a quiet background. Since amplitude compression is a nonlinear process, it is potentially very damaging to sound quality. Three physical parameters of the compression process were investigated for their influence on sound quality: the degree of compression. a time constant for sound reduction, and a time constant for sound enhancement. A subjective, multidimensional comparison experiment with several subjects suggested that only the two first named are perceptually significant. By means of a multidimensional scaling experiment, with the original (uncompressed) signal as a reference, optimum values were determined for these parameters in two simulated acoustic environments. Finally, these optimal values were tested with a variety of music material.