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The thon and rammana (Khmer: ស្គរថូននិងស្គររមនា; Thai: โทนรำมะนา, pronounced [tʰoːn ram.ma.naː]) are hand drums played as a pair in Khmer and Thai classical music. It consists of two drums: the thon (Khmer: ស្គរថូន;Thai: โทน), a goblet drum with a ceramic or wooden body and the rammana (Khmer: ស្គររមនា;Thai: รำมะนา), a small rebana-typed frame drum or tambourine. They are used usually in the Mohaori ensemble in Cambodia and khruang sai ensemble in Thailand. The thon gives a low pitch and the rammana gives a high pitch.
Earlier in the 20th century, the thon and rammana were sometimes played separately.
Khean, Yun; Dorivan, Keo; Lina, Y; Lenna, Mao. Traditional Musical Instruments of Cambodia (PDF). Kingdom of Cambodia: United Nations Educational, Scientific and Cultural Organization. pp. 248–253.
"The Flute Player". pbs.org. Retrieved 10 October 2018. Thaun, a goblet drum, is similar to the skor arakk, except it has a shallower head and a slimmer body...used as part of a two-piece drum set in the mohori ensemble...