Most of the initial consonants that preceded the vowel were either bilabial or dental-alveolar and were either stops or fricatives.
In this case, it is the bilabial nasal from the initial of the plural character men3.
Both cases involve a preceding alveolar nasal and a following bilabial plosive.
If a word contains an /m/, will there be another bilabial consonant following in the word?
For example, the primary gesture for m is the closure of the lips, hence the place of articulation is bilabial.
I reached back into my undergraduate memory and remembered the phonetic symbol for the bilabial fricative and gave it my own personal phonemic status - /ph/.
These include bilabial, palatal, and velar fricatives as well as labio-dental glides and glottal stops.
The cues of the velar stop are, however, preserved in the formant transitions into the following bilabial nasal.