I just imported a Vietnamese Northern (Hanoi) dialect dictionary. You can download the dictionary. I imported it as HTK lexicon. This is the result:
It looks fine. Here is a small excerpt:
mà [mà] m aa2
má [má] m aa3
mả [mả] m aa4
mã [mã] m aa5
mạ [mạ] m aa6
ma [ma] m aa7
If you speak the Vietnamese language, you should get the concept. The different a-vowels are different phonemes (aa2, aa3, aa4, aa5, aa6, aa7). This approach should be OK.
It would be nice if a native speaker would try to record a few Vietnamese words with simon:
It would be interesting to know whether it works since Vietnamese is completely different from English. I recommend that you try to record 10 different Vietnamese words with simon (each word 8 times).
Tags: HTK, vi, Vietnamese