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Musical instrument
The phin pia is a chest-resonated stick zither with two to five strings. It is considered the national instrument of Northern Thailand. The one string version (equivalent to the Cambodian Kse diev) is the phin namtao.
References
McGraw, Andrew (Summer–Fall 2007). "The Pia's Subtle Sustain: Contemporary Ethnic Identity and the Revitalization of the Lanna "Heart Harp"". Asian Music. 38 (2): 115–142. doi:10.1353/amu.2007.0035.