Pronunciation of can/can't

[Rudolph C Troike]

In stressed use, in some varieties the vowel is nasalized in both, with
minimal articulation of the /n/, but the vowel may be longer in duration
in CAN than in CAN'T, so that length may be the distinguishing (and hard
to detect) feature. (Of course, CAN'T may end in a glottal stop, also not
audible per se.) This is probably why they are perceptually so close for
Mai.
        In British (and probably declining Eastern New England) speech,
CAN'T has an /a/ vowel, and in many Southern US varieties, CAN is most
often unstressed with a high-central ("barred i") vowel, or even /I/,
while CAN'T usually carries more stress and frequently has /aey/ or /ey/
as the vowel nucleus (represented orthographically as "cain't").
        Gratitude to Arnold for his enlightening excursion into protasis
use of "can't". I'll have to see if I can't come up with a counterexample.
        --Rudy