Munch your bag lunch to the beat of the blues. Or carry out at noontime to the tune of your favorite popular songs.

For the second summer season, free mid-day outdoor concerts are celebrating the successful revitalization surrounding Franklin Square Park in the heart of downtown.

"It's part of the entire renaissance of the area," said Dorothy Callaghan of the Franklin Square Association, a volunteer citizen's group that sings the praises of urban redevelopment. "With the enormous amount of development going on and the increasing number of people, we're concerned with making it into a pleasant environment for them to work in."

Each Tuesday and Thursday from just before noon until 1:30 p.m., through mid-August, the city's largest park -- stretching across 4.8 acres between 13th and 14th and K and I streets -- comes alive with people and performers.

This week, the rocking Rhythm Masters of Bethesda promise blues "for your heart and soul" on Tuesday. Another local artist, popular songs soloist Christina Spink, will entertain Thursday.

The shows, which are backed by the District of Columbia government and the local unit of the American Federation of Musicians, may be expanded to every weekday lunch hour, Callaghan said, if enthusiastic volunteer musicians come through on their offers.