When faced with the daunting prospect of analyzing a dozen beautifully reissued CDs of Indonesian music -- all originally released between 1967 and 1989 as part of the groundbreaking Nonesuch Explorer series -- the best place to start is with the monkey chants. Side Two of "Golden Rain" has, since its original release in 1969, been an essential introduction to the freakier side of "world music." Indonesian music has a well-deserved reputation as elegant and ethereal, dependent on chiming gamelan and delicate female voices. The other 11 discs in this Explorer reissue series adequately chronicle that aspect, as does Side One of "Golden Rain," which contains an explosive, gong-based piece and a stately dance piece that are quite reflective of indigenous styles. Side Two -- the infamous Side Two -- is given over to a ketjak piece, "The Ramayana Monkey Chant": 22 minutes of frenzied chest-beating, chanting, grunting, ground-thumping and general mayhem orchestrated by a chorus of nearly 100 men and a dozen or so solo singers and dancers. The monkey chant is a creation of this century, designed to entertain tourists. But unlike hula lessons, the ketjak can permanently warp your little Western mind.