basso profondo
The lowest and deepest bass voice classification, capable of reaching notes below the bass staff
In Depth
Basso profondo voices can produce pitches as low as C2 or even lower, with a dark, resonant quality that gives unusual weight to the bottom of a choral or operatic texture. The voice type is prized in Russian Orthodox choral music, where basses regularly sing down to B♭1. In opera, basso profondo roles include Sarastro in The Magic Flute and the Commendatore in Don Giovanni. The voice type requires exceptional natural depth rather than trained extension.
Some Russian basso profondos, trained in the Orthodox church tradition, can produce usable notes as low as G1 — nearly at the threshold of human pitch perception.