quartet, a musical composition for four instruments or voices; also, the group of four performers.

How many members does a quartet have?

In music, a quartet or quartette (French: quatuor, German: Quartett, Italian: quartetto, Spanish: cuarteto, Polish: kwartet) is an ensemble of four singers or instrumental performers; or a musical composition for four voices or instruments.

How many is a quintet?

quintet, a musical composition for five instruments or voices; also, a group of five musicians performing such a composition.