A bass is a male singer who sings in the deepest vocal range. According to Grove Music Online, a bass has a range extending from around the F below low C to the E above middle C (i.e., F2–E4), with a tessitura or comfortable range normally ranging between G2 (G below low C) and A4, which are the outermost lines of the standard bass clef. However, cultural influence and human uniqueness create a wide variation in range and quality, and parts for basses have included notes as low as the C two octaves below middle C (i.e. Measure 12 of Ne Imami Iniya Pomoshchi by Pavel Chesnokov), and the Rachmaninov Vespers call for the B-flat a tone below that. Many basses have trouble reaching those notes, and the use of them in works by Slavic composers has led to the colloquial term "Russian bass" for an exceptionally deep-ranged basso profundo that can easily sing these notes. They also have trouble reaching the notes above middle C, according to Grove Music Online, however many British composers such as Benjamin Britten have written parts for bass that center far higher than the bass tessitura (such as the first movement of his choral work Rejoice in the Lamb). The Harvard Dictionary of Music defines the range as being from the E below low C to middle C (i.e. E2–C4). Ranges Guide, Yale University Music Library, taken from the Harvard Dictionary of Music

It is also common for men who are classified as "basses" (and have a full bass choral range) to have a speaking voice which may sound much higher than would be expected.

The bass voice is used differently in different choral traditions. For example, in the United States, no distinction is usually made between bass and baritone voices, which overlap at all but the extremes of their respective ranges. The exception is in arrangements for male choir (TTBB) such as barbershop quartets, which generally make separate mention of bass and baritone as the lowest two parts. In practice, however, basses have a darker vocal colouration. In the Russian choral tradition the bass is called upon to sing pitches well below the baritone range, as noted earlier with reference Chesnokov and Rachmaninoff.