1) Contrabass instrument 2) Double-bass 3) Low-pitched 1) Contrabasso 
Contrabass (derived from contrabbasso) refers to a musical instrument of very low pitch; generally those pitched one octave below instruments of the bass register. While the term most commonly refers to the double bass (which is the bass instrument in the orchestral string family, tuned lower than the cello), many other instruments in the contraba...
• (n.) Double bass; -- applied to any instrument of the same deep range as the stringed double bass; as, the contrabass ophicleide; the contrabass tuba or bombardon. • (n.) The lowest stringed instrument of the violin family.
(from the article `saxhorn`) ...where they are not known as saxhorns but simply as alto in E (in Britain, tenor horn), tenor in B (baritone), the wider-bore baritone in B ...
Con`tra·bass' noun (Mus.) Double bass; -- applied to any instrument of the same deep range as the stringed double bass; as, the contrabass ophicleide; the contrabass tuba or bombardon. Con`tra·bass' noun (Mus.) The lowest stringed instrument of the violin family. 
In music contrabass or double bass is a term applied to any instrument of the same deep range as the stringed double bass; such as, the contrabass ophicleide; the contrabass tuba or bombardon.
[adj] - pitched an octave below normal bass instrumental or vocal range
double-bass adjective pitched an octave below normal bass instrumental or vocal range; `contrabass or double-bass clarinet`