MUSIC

The boards of the Master Chorale of Orange County and the Pacific Chorale have voted to merge the two organizations, informed sources have reported. The new chorale will be in place for the 1989-90 season, the sources said. John Rhynerson, chairman of the Master Chorale board, would confirm only that “a merger concept” had been approved that would affect the groups “financially and operationally. But,” he stressed, “artistic direction and artistic staff has not been determined. We expect to make an official statement” later this week when the board meets again. Pacific Chorale chairperson Anne Nutt could not be reached for comment. Merger talks have been going on since January, sparked by increasing competition for donations and by the hope that consolidating audiences would make it easier to fill the 3,000-seat Segerstrom Hall at the Orange County Performing Arts Center in Costa Mesa.