This talk evaluates two conflicting views on Italian gemination, e.g. /fato/ ‘fate’ vs. /fatto/ ‘fact’: the mainstream ‘duration-only’ picture, positing that gemination involves an essentially duration-based contrast, and the ‘alternative picture’, identifying systematic non-durational acoustic co-variants, likely linked to increased consonant constriction strength and laryngeal tension in geminates. It comprehensively examines temporal and non-temporal acoustic parameters across three regional varieties: Veneto (north), Rome (centre), and Calabria (south).

For stop consonants, linear mixed models confirm expected temporal differences while revealing a significantly longer post-release phase (PRP) for geminates in some cases. Crucially, non-temporal effects are also significant: geminates exhibit higher fundamental frequency (f0) in flanking vowels, lower closure voicing proportions, as well as significantly higher intensity differences in C(ː)V intervals (IntDiff) and maximum intensity-envelope velocity within the same intervals (MaxVel), indexing increased constriction strength. Voiceless geminates also show higher H1*-H2* values at V2 onset and a similar tendency at V1 offset, suggesting increased breathiness likely driven by higher laryngeal tension through glottal opening. Random Forest classification demonstrates that while durational parameters alone yield 94.5% accuracy, non-temporal cues independently achieve 80.2% accuracy, driven primarily by IntDiff.

The analysis further examines voiced labiodental fricatives (/v/ and /vː/), revealing extensive allophonic variation. Singleton /v/ frequently surfaces as a weakened approximant [ʋ] (47%), whereas the geminate /vː/ frequently exhibits a strengthened, often plosive-like ([b̪ː]), realisation (36%).

Ultimately, the systematic co-variation of constriction strength and laryngeal tension challenges the ‘duration-only’ consensus. These findings raise and echo theoretical questions regarding whether phonological representations of Italian gemination must be enriched beyond standard timing structures to account for these robust non-temporal mechanisms.