Otogakure

Otogakure (音隠れの里, Otogakure no Sato; Literally meaning "Village
Hidden in Sound"), called Oto for short, was Orochimaru's personal
village, founded for the express purpose of collecting ninja for his
experiments and his quest to learn all jutsu. In actuality, Oto is not
really a village, but a group of hideouts and bases scattered
throughout the Land of Sound and other countries. Three Sound ninja
(Dosu Kinuta, Zaku Abumi, and Kin Tsuchi), under Orochimaru's orders,
entered the Chunin Exam with the goal of killing Sasuke Uchiha.
However, Orochimaru was actually using them as test subjects for
Sasuke's power after Orochimaru gave him the Cursed Seal. Sound ninja
use a diverse amount of jutsu. The Oto symbol is an eighth note.