adjective
sonorous
SAH-ner-uhs/ˈsɑːnərəs/
Having a deep, rich, resonant sound.
The massive bronze bell gives a deep, sonorous tone.

Etymology
Latin sonorus meant “resounding,” expressing more than simply making a noise. English preserves that emphasis on resonance and fullness in describing a deep, rich sound.
In context
He then sang these words in a deep and sonorous bass, which the dragon had no difficulty in hearing.
More examples
- A sonorous bell marks the hour.
- The cello adds a sonorous bass line to the melody.
- I recognize the narrator by his sonorous voice.
Forms
sonorous
sonorously adverb — With a deep, rich, resonant sound.
sonority noun — The quality of a rich, resonant sound.