Many of us may be familiar with the erhu, an ancient Chinese instrument, and not even know it. Its hauntingly expressive sound, much like a woman's voice, has graced nearly two dozen film scores in the past 20 years, movies like "Mulan 2," "Anna and the King," "The Joy Luck Club" and "The Passion of the Christ."

	Karen Han will play the erhu on Saturday night. Click photo for larger image. HarmoniZing! Where: Pittsburgh High School for the Creative and Performing Arts on Ninth Street. When: Saturday 8 p.m. Tickets: $15-$20; $50 for a VIP reception. 412-344-5628.

Behind all of these films is Karen Han, an acknowledged virtuoso who will be adding the upcoming "Memoirs of a Geisha" to her list. It is Pittsburgher Rob Marshall's follow-up to his Academy Award-winning "Chicago" and stars Ziyi Zhang ("Crouching Tiger, Hidden Dragon," "House of Flying Daggers"), Academy Award nominee Ken Watanabe ("The Last Samurai") and Li Gong ("Farewell My Concubine," "Raise the Red Lantern"). Internationally acclaimed cellist Yo-Yo Ma and violinist Itzhak Perlman are also featured on the John Williams' soundtrack of a movie that is already generating Oscar buzz.

The local group, HarmoniZing!, will present Han at Pittsburgh High School for the Creative and Performing Arts on Saturday, along with Pittsburgh Ballet Theatre principal dancers Ying Li and Jiabin Pan, Chinese traditional dancer Yanlai Wu, pianist Yeeha Chiu and flutist Barbara O'Brien.

Although Han didn't originally record the surprise hit "Crouching Tiger, Hidden Dragon" (its poetic melodies were played by Ma on cello), composer Tan Dun, winner of both an Oscar and a Grammy for original score, rewrote the cello solos specifically for Han in a new "Crouching Tiger, Hidden Dragon Concerto for Erhu and Chamber Orchestra." She will play the fourth of six movements with the CAPA orchestra, along with several other pieces on the program.

Although the concerto is full of technical difficulties, Han never tires of the instrutment that she calls "my friend ... my lover. It is music from the heart," she says. "It has a very beautiful and deep soul and is more emotional than the violin."

Han began studies with her father at a young age, before being one of two selected from 1,000 applicants to the Central Conservatory of music where she graduated with honors. She is also only one of three musicians in China who have a master's degree on erhu.

The instrument is played on the left knee in a vertical position. Generally shaped like a violin, it has a longer neck with a small sound box at the bottom. There are only two strings that float above the neck and the bow is attached around them so that it cannot be removed. The fingers touch the string lightly to produce different pitches. But because there are only two strings, Han must make large leaps in producing a melody or moving through technical passages.

"It is horrible," she insists. "I go up and down, up and down all the time. But the music represents life -- not only the beauty, but the down times."

Even though she loves the classical heritage of the erhu, Han still relishes meeting the new technical standards that contemporary composers have discovered. "I love the challenges that they present," Han says breaking into a lovely melody from "Crouching Tiger" with a voice that is uncommonly sweet.

And it's easy to hear, even over the telephone, just where the music starts -- indeed, right from the heart.