bass part; bass line
Refers to the lowest part in a musical piece, such as a bass line in a choir or instrumental arrangement. Used in musical contexts.
In a choir, the bass part supports the overall sound.
The bass line of this piece is very simple.
バス is a more common loanword for 'bass' in music, while 最低音部 is a technical term often used in scores or formal descriptions.
低音部 means 'low-pitched part' and is broader; 最低音部 specifically means the lowest part.
Compound of 最低 (lowest) + 音部 (sound part). A straightforward technical term in music.