UNDER the baton of renowned English conductor Anthony Inglis, the Hongkong Sinfonietta will present an evening of harmonious music at the City Hall Concert Hall at 8 pm on April 25. Inglis, who started to conduct at the age of six, has conducted many of Britain's best-known orchestras including the Royal Philharmonic Orchestra, the Philharmonia, the Halle Orchestra and the English Chamber Orchestra, and in numerous world-class venues in Belgium, Canada, Italy and Austria. In 1990, Inglis was invited to conduct the Royal Air Forcenevolent Fund's concert with the Royal Philharmonic Orchestra and the Central Band of the Raf to commemorate the 50th anniversary of the battle of Britain. Inglis is the music supervisor of the theatrical work, The Phantom of the Opera , in London as well as the conductor of Benjamin Britten's The Young Person's Guide to the Orchestra . Accompanied by piano soloist Eva Lue, the orchestra will give its renditions of David Gwilt's Colloquiem For Small Orchestra , Mozart's Piano Concerto No. 22 in E flat and Brahms' Symphony No. 2 in D. OP. 73 . Tickets for the Urban Council presentation priced at $40, $55 and $70 (half-price for students and senior citizens) are available all URBTIX outlets. For telephone reservation, call 7349009. For more information, call 7342006.