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Formant frequencies

Definition

Resonance frequencies of the vocal tract that shape vowel quality. F1 and F2 (the first and second formants) are the most informative for speaker comparison because they reflect both vocal tract anatomy and learned articulation habits.

Related terms

Forensic speaker comparison
A systematic examination comparing acoustic and phonetic features of a questioned voice recording against known reference recordings of a named individual, expressed...
I-vector / x-vector
Fixed-length mathematical representations of a speech utterance used in automatic speaker recognition. I-vectors are derived from Gaussian mixture model statistics; x-vectors are...
IAFPA
International Association for Forensic Phonetics and Acoustics: the primary professional body for forensic phoneticians and audio analysts, which publishes guidelines on speaker...
Likelihood ratio (LR)
The ratio of two conditional probabilities: the probability of the observed evidence given the prosecution's hypothesis (same source), divided by the probability...
PLDA (Probabilistic Linear Discriminant Analysis)
A statistical back-end model used with i-vector and x-vector systems to compute a similarity score between two utterance representations, normalised for within-speaker...

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