ðə stˈæɾəs ʌvðɪ ˌɑːpəzˈɪʃən bᵻtwˌiːn lˈɔŋ ænd ʃˈɔːɹt vˈaʊəlz ɪz nˌɑːt ɛntˈaɪɚli klˈɪɹ, bˌʌt ɪɾ ɪz nˈoʊn fɔːɹ sˈɜːʔn̩ ðˌɐɾɪt dʌznˌɑːt kˈiːp ðə pˌiːˌaɪˈiː kˈɑːntɹæst ɪntˈækt, æz hˈɪɾaɪt spˈɛlɪŋ vˈɛɹiz ɪn ɐ wˈeɪ ðæt mˌeɪks ɪt vˈɛɹi hˈɑːɹd tʊ ɪstˈæblɪʃ wˈɛðɚ vˈaʊəlz wɜːɹ ɪnhˈiəɹəntli lˈɔŋ ɔːɹ ʃˈɔːɹt.
The status of the opposition between long and short vowels is not entirely clear, but it is known for certain that it does not keep  the PIE contrast intact, as Hittite spelling varies in a way that makes it very hard to establish whether vowels were inherently long or short.