The ‘telephone effect’ on formants: a response

This article is a response to Hermann Kunzel’s article ‘Beware of the telephone effect”: the influence of telephone transmission on the measurement of formant frequencies’ (Forensic Linguistics 8(1), 80–99). There, he shows convincingly that the evaluation of formant frequencies, notably F1, is affected by the band-pass filter effect of telephone transmission. This response does not question his data, or cast doubt on the general lesson to be drawn on the need for caution in estimating formant frequencies from telephone speech, or engage with the issues of dialectological methodology with which he is in part concerned, but it does challenge the apparent strength of the conclusion he draws for forensic speaker identification (FSI). His conclusion could be read as endorsing a complete exclusion of formants from the FSI process, and his article will, I fear, be misinterpreted by some as justification for setting aside a valuable source of speaker-characterizing acoustic information in FSI.