Certain researchers indicate a pattern in Neapolitan where the [a] vs [ɑ] sounds are used somewhat interchangeably. Though they are not phonemes, they are socially stigmatized allophones denoting certain classes less privileged than others.

While they are in free variation, there are also some examples of where they are placed in contrast:

[ma] for ma' vs. [mɑmɑ] for màmma