This language gets by with just 11 distinct sounds

Rotokas, spoken by a few thousand people on the island of Bougainville in Papua New Guinea, has one of the smallest sound inventories of any known language: just 6 consonants and 5 vowels. By comparison, English uses around 44 phonemes and some languages use well over 100. Rotokas even manages without the sounds S, F or Z, which most languages consider practically essential.

— Wikipedia contributors, Rotokas language — Phoneme inventory of Rotokas