Gamelan outside Indonesia gave a new impetus to the performance of gamelan and Javanese dance in the Netherlands. Together with Mr and Mrs Ronosuripto, the Amsterdam Gamelan group played many concerts and performances with Javanese dance and shadow puppetry (wayang kulit). Rien Baartmans, who as a child had been taking lessons from Bernard IJzerdraat, studied wayang and kendhang with Pak Ripto, which very much stimulated his own group Ngesthi Raras in Haarlem. In 1978 the new gamelan society Naga, founded by Rob van Albada, acquired a gamelan from Solo. This gamelan was used by several groups, performing traditional and modern music for gamelan.
Gamelan interference beats are meant to give the listener a feeling of a god's presence or a stepping stone to a meditative state. The scale roughly approximates that of the phrygian mode of the Western major scale (E-E on the white keys of the piano), with the notes EFGBC corresponding to the note positions 12356 in the "slendro" scale used by most gamelan. As well as the non-western octave and the use of beats, Javanese gamelan uses a combination of tempo and density known as "Irama", relating how many beats on the "saron panerus" instrument there are to notes in the