The sueng (Thai: ซึง, pronounced [sɯ̄ŋ], also spelled seung or süng) is a plucked fretted lute from the northern region of Thailand. The instrument is made from hardwood and its strings (numbering either four or six and arranged in courses of two) are most often made of steel wire. It has nine bamboo frets.
The sueng is part of a northern Thai traditional ensemble called the salo-so (saw)-sueng ensemble, along with the salo (3-string spike fiddle) and pi so (free reed pipe).
Most suengs are made from a single piece of Jackfruit wood, carved into shape by the artisan. Once carved, a round sound board of the same wood is glued to the instrument. Trapezoid shaped sticks are cut form a bamboo stem and installed as frets. The tuning pegs are then installed: this pegs only have an aestethic funcion nowadays, as many modern suengs rely on guitar machine heads for tuning. Eventually the instrument is painted and sometimes decorated with Lai Thai motifs. The bridge can be made from either bone or hardwood. Another wood used for the construction of the sueng is Rosewood.
The frets on the sueng are spaced differently than western fretted instruments. In fact, with such arrangement of frets, the instrument plays in the 7-TET temperament, meaning that in one octave the instrument plays seven tones, as opposed to the twelve tones of western music. This temperament is found troughtly in traditional Thai music and in other instruments like Ranat.