Bass (/beɪs/ BAYSS) (also called bottom end)[2] describes tones of low (also called "deep") frequency, pitch and range from 16 to 250 Hz (C0 to middle C4)[3] and bass instruments that produce tones in the low-pitched range C2-C4. They belong to different families of instruments and can cover a wide range of musical roles. Since producing low pitches usually requires a long air column or string, and for stringed instruments, a large hollow body, the string and wind bass instruments are usually the largest instruments in their families or instrument classes.