Resonant describes sound that is deep and rich. It also can mean deeply evocative. A resonant speech moves you by bringing to mind all that is good in the world: family, friends, laughter.
Resonant comes from the Latin re, meaning again, and sonare, meaning to sound––or literally to sound again or echo. So resonant's meanings all have that sense of reverberating or echoing. Not only does it mean echoing or evoking meaning, but it also refers to sound that echoes through a room. Don't confuse the spellings of resonant (the adjective) and resonate (the verb).