MUSIC

Mester to Conduct Down Under: Jorge Mester, 55, will become chief conductor of the West Australian Symphony Orchestra in early 1991. The Pasadena Symphony music director led the 85-member orchestra during two Perth Concert Hall performances last weekend. Robert McMullin, Pasadena Symphony executive director, said that because the Australian musical season is opposite the United States’, Mester’s three-year appointment will not interfere with his Pasadena Symphony duties.