The American a seems to be a centralized ä (in IPA) not A(x-sampa) or the Japanese / latin [a] but I can't find a way too mark centralized x-sampa vowels... maybe a: though technically that means a longer [a] not ä... but given that UTAU already has symbols for conveying length of vowels via the piano roll, any long vowels aren't necessary. It also solves the fact that I can't umlaut a consonant for centralized V.... 'V:'... I've long been planning a list with reduced vowels, 1, 8, and }. I've also noticed that with narrow transcriptions, Ii and Uu are common occurrences in pronunciation...
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