Towards a mapping of timbral space

This paper presents the interim findings of a series of listening tests designed i) to test the extent to which the relative positions of sounds inhabiting a simple three dimensional co-ordinate space, whose axes are formant centre frequencies, are reflected in perceptual distances between those sounds, and how this varies through the space, ii) to establish the perceptual granularity of the space – how the maximum distance between two sounds in the space where no difference can be heard varies throughout the co-ordinate space, and iii) the extent to which the results of i) and ii) corelate. The paper concludes that, firstly, subjects are in general, able to perceive relative distances in this co-ordinate space, and that ability varies throughout the space , and that secondly, the ability to discriminate timbral shifts varies quite considerably in the space. In both cases, the shift in the second formant centre frequency seems to be salient; some errors in test data, however, prevent any firm conclusion on the extent to which the results of i) and ii) corelate. The purpose of this study is to provide empirical data to inform the development of more intuitive user interfaces for timbre specification