This empirical study is concerned with examining the relation between tempo and expressive timing in music performance. The participants were asked to listen to ten sound examples (in their genre of preference) and to indicate which example was an original recording and which was a tempo-transformed version (i.e., a slowed-down or speeded-up version of the original).

Two hypotheses will be considered: the relational invariance hypothesis and the tempo-specific timing hypothesis. The first hypothesis predicts no significant difference in responses to the original and tempo-transformed excerpts: both excerpts will sound equally natural, so that the respondents will consider both versions musically plausible performances, and, consequently, just guess what is an original recording. The second hypothesis is based on the idea that expressive timing in music performance (defined as the local deviations from isochrony and/or more global changes in tempo) is intrinsically related to global tempo. When expressive timing is simply scaled proportionally to another tempo this may make the performance sound awkward or unnatural, and hence easier to identify as an tempo-transformed version.

The results of a pilot study (N=307) indicate that a significant majority of the participants could indicate what was as an original and what a tempo-transformed version. The results suggest that expressive timing can function as a clue in identifying a real performance. These results are discussed in the context of whether there is perceptual invariance of expressive timing under tempo transformation.