The Effect of MP3 Compression on the Timbre Space of Sustained Musical Instrument Tones
Chung Lee, Andrew Horner, Bin Wu · Rare & Special e-Zone (The Hong Kong University of Science and Technology) · 2013
Previous studies related to MP3 compression have investigated the discrimination of compressed instrument tones. However, these studies have not considered the effect of MP3 compression on the timbre space. In the current study, in a triadic listening test subjects were asked to rate the dissimilarity of all pairs of eight original instrument tones from various instrument families. The same process was repeated on MP3-compressed tones using various bit rates (32, 64, and 128 Kbps). The results showed strong correlations between the dissimilarity scores of the original and compressed tones, indicating relatively subtle perceptual changes overall. The 2-D multidimensional scaling solutions for tones compressed with bit rates of 64 and 128 Kbps were very similar to the original but the coordinates changed more dramatically for a bit rate of 32 Kbps (especially in the saxophone), indicating a change in the underlying timbre space for low bit rates.