“…Standard German comprises a set of eight tense monophthongs, i.e., [iː,eː,ɛː,ɑː,oː,uː,ʸː,øː] and seven lax ones, i.e., [ɪ,ɛ,a,ɔ,ʊ,ʏ,œ], as well as [ə] and [ɐ], which only occur in unstressed syllables. The tense monophthongs are generally longer and more peripheral in the vowel space than their lax counterparts, although [ɑː] and [a] only differ in terms of duration (Jørgensen, 1969; Antoniadis and Strube, 1984; Bohn and Flege, 1990, 1992). In spectral terms, German distinguishes the five front unrounded vowels [iː,eː,ɪ,ɛː,ɛ], the four back rounded vowels [uː,ʊ,oː,ɔ], the four front rounded vowels [ʸː,ʏ,øː,œ], the two central vowels [ə,ɐ], and the two open vowels [ɑː,a].…”