Abstract:
A single even harmonic added to an odd-harmonic complex may be judged as more salient than its odd neighbors in a clarity rating task [Roberts and Bregman, J. Acoust. Soc. Am. 90, 3050--3060 (1991)]. For a fundamental frequency (F0) of 100 Hz, this even--odd difference was evident for the highest even harmonic tested (harmonic 8) despite its marginal resolution. This study used similar complexes in a 2IFC procedure. Each interval consisted of a complex tone followed by a pure tone. The frequency of the pure tone matched that of a harmonic in the complex in one interval and was changed by (plus or minus)0.5*F0 in the other. Subjects were instructed to identify the matching interval. Since the pure tone was heard after the complex tone, it could not cue listening to a particular frequency region. Cross-interval cuing was prevented by changing F0 between the intervals. The procedure used was intended to maximize the effects on performance of differences in immediate perceptual salience between the harmonics. The added even harmonic was typically judged with greater accuracy than its odd neighbors. Furthermore, accuracy declined with increasing harmonic number only for the odd harmonics tested. [Work supported by BBSRC, UK.]