A perception experiment based on systematic variation of disyllabic vowel duration and vowel quality, and of intervocalic fricative duration in the German minimal lexical stress pair 'Kaffee “coffee” vs. Ca'fé (locality) in a low f0 tail or a high f0 plateau shows highly significant effects of the 3 variables as cues to lexical stress. The combined vowel quality and fricative variables outweigh vowel duration. The effect of the prosodic frame is marginal. It is concluded that acoustic stress variables do not form a generally valid cue hierarchy.

Index Terms: lexical stress, accent, perceptual hierarchy