The sound vibration of the Hare Krishna mantra, although presented in the ordinary alphabet, should not be taken as mundane or material.
Srimad bhagavatam 4.9.4,
Everything in Material world is temporary.
False Happiness in the material world is the source of distress.
This material world is actually meant for misery, just as a prison house is meant for punishment.
Material world is like a dream.
Material world brings pleasure and miseries.