BEFORE the Philadelphia Orchestra departs on a three-week visit to Asia with Yannick Nezet-Seguin, making his first tour with the musicians, they're offering six free programs throughout the region.

Designed to reach audiences in different venues, and in collaborative participation with other organizations, the week could be seen as a present to the public after Yannick's second season here. To make that gift, the 95-member ensemble will split into smaller groups, the better to reach more neighborhoods.

A "Messiah" sing-in and a final concert at the Navy Yard require reservations (philorch.org). But all programs are free, and the others are on a first-come, first-served basis.

* May 12: Orchestra flutist Loren Lind, storyteller Charlotte Blake Alston and pianist Graeme Burgan offer a 45-minute interactive program for ages 3 to 5. Central Library Auditorium, 19th and Vine streets, 11 a.m.

* May 13: Two youth orchestras - Tune Up Philly and Philadelphia Regional Youth String Music (PRYSM) - play works by Paul Smith, Leroy Anderson and Mozart with their Philadelphia Orchestra counterparts, led by associate conductor Christian Macelaru. Salvation Army Kroc Center, 4200 Wissahickon Ave., 4 p.m.

* May 14: Vocalists can bring their "Messiah" scores and participate in a sing-in, teaming up with orchestra, soloists from the Academy of Vocal Arts and the Mendelssohn Club Chorus.

Michael Rossi leads Part 1 and the "Hallelujah" Chorus from Handel's classic, along with his "Water Music." Reserve free ticket at philorch.org, where "Messiah" vocal parts are also available via download. Perelman Theater at the Kimmel Center, Broad and Spruce streets, 6:30 p.m.

* May 14: The orchestra performs a side-by-side rehearsal with the Lower Merion Symphony. Orchestra assistant conductor designate Lio Kuokman leads Bizet's Symphony in C and Ravel's "Bolero." Harrington High School, 600 N. Ithan Ave., Rosemont, 7:30 p.m.

* May 15: Kuokman leads the Fab Philadelphians in music of Grieg, Mozart and Dvorak. Market and Shops at Comcast Center, 1700 JFK Blvd., noon.

* May 15: Kuokman conducts the orchestra in music by Tchaikovsky, Waldteufel, Dvorak, Smetana and Johann Strauss. Urban Outfitters Headquarters at the Navy Yard, Building 543, 16th Street and Flagship Avenue, 6 p.m.: Reserve free ticket at philorch.org.