This annual Juilliard School festival, organized by Joel Sachs, is an opportunity to focus, as it were, on a particular place and time, and this year, the theme is "Nippon Gendai Ongaku: Japanese Music Since 1945." It opens with a program of works for chamber orchestra by Toshio Hosokawa, Akira Nishimura, Somei Satoh and others, and continues with four chamber-music events and a closing concert (Jan. 30) by the Juilliard Orchestra, conducted by Tadaaki Otaka, that features a tribute to Toru Takemitsu. All concerts are free, but tickets are required.