Telephone speaker recognition amongst members of a close social network

Abstract

This article presents results from a speaker recognition task carried out by a close-knit network of speakers (university friends who have lived in shared accommodation with each other for two years). Ten male speakers recorded a scripted message on to an answer machine via a mobile telephone. Two foil speakers from outside thenetwork were also recorded. Samples of between 8 and 10 seconds were extracted from all twelve recordings, and used as stimuli for an open speaker recognition test performed by the network members. Listeners varied widely in their performance, and one listener failed to recognize his own voice. Some of the voices were easy to identify, but several speakers were consistently misidentified, and one speaker was particularly hard to identify. Both of the foil speakers were sometimes mistaken for network members Auditory analysis of the voices shows, as expected, that speakers with the most distinctive regional accents and other idiosyncratic features were the most consistently identified. Acoustic analysis of F0 was also undertaken. It was found that the speakers who were most consistently identified were those with relatively high and low mean F0 values, as well as those with the widest and narrowest overall F0 range. Speakers with average pitch values and ranges in the middle of the overall group values proved harder to identify. The findings support the view that average pitch is a robust diagnostic of speaker identity, not only for forensic phoneticians, but also for naive listeners. They furthermore demonstrate that naive speaker recognition, even among members of a close-knit social network, is not a task which can be achieved infallibly.