The quality of being full, deep, and loud in sound.
Sonorousnesses are usually thought of as a good thing, like the sound of a big bell.
Examples:
The sonorousnesses of the church bells filled the whole town.
I love the sonorousnesses of the big drum.
The sonorousnesses of his voice made everyone stop and listen.
The sonorousnesses of the thunder scared the little dog.
The sonorousnesses of the opera singer's voice filled the whole theater.
The sonorousnesses of the gong echoed through the whole room.