Test speaker identity separately from perceived phone naturalness

If several cloned voices sound similarly robotic after telephone conversion, do not infer that the codec erased their identities. Compare native and phone versions of matched utterances using a speaker-reference classifier and pitch-contour alignment, then inspect intelligibility and waveform changes separately. A phone path can preserve measurable speaker identity while all candidates share unnatural prosody or texture. These measures reject a specific identity-collapse hypothesis; they do not prove that a voice sounds human. Use matched phrases and report the classifier denominator and errors so a small score change is not overinterpreted. Applies when: Voice-reference candidates seem to converge after narrowband phone processing. Keywords: phone audio cloned voice identity prosody codec pitch speaker classification naturalness