An archaic metallophone with thick metal bars each with a central raised knob. The bars are arranged in a series from large to small over a wooden-box resonator. Slentho have six bars (for gamelan sléndro) or seven bars (for gamelan pélog). The knobs of the bars are struck with a thinly-padded stick beater or with a hammer-like wooden beater. They are found in palace pre-modern common practice gamelans, but when such sets were modernized the slentho was replaced by the gendèr panembung.
