Which chakras are affected by the vibrations of A, U, and M, and how can they be used by a seeker?

According to Osho, A resonates in the navel/solar plexus (manipura) and awakens the lower centers; U vibrates the heart and throat (anahata–vishuddhi); M hums in the head, focusing the third eye (ajna); the ensuing silence opens to the crown (sahasrara). A seeker should chant each sound while remaining a detached witness, avoiding trance—letting sound refine the chakras while staying alert in the silence.

Chant A in the belly, U in the chest/throat, M in the head—then rest in the quiet—while staying awake inside, not dreamy.