Little is known about intraspeaker changes in voice across changing speaking situations in everyday life. In this study, we examined acoustic variations between and within 5 talkers and their effect on the likelihood that voice samples would not be identified as coming from the same talker. Talkers were drawn from a large database recorded to capture everyday variations in vocal characteristics. Nine samples of /a/, recorded on three different days, were examined for each talker. Acoustic characteristics were estimated using VoiceSauce and analysis-by-synthesis, and listeners judged whether pairs of voices came from the same or two different talkers. Results indicate that interspeaker variability in voice quality exceeds intraspeaker variability, but differences are smaller than expected. As predicted by models that treat voice quality as an auditory pattern, the acoustic attributes associated with incorrect “different speaker” responses varied from talker to talker, depending on the particular characteristics of the voice in question.