They had a double-bass ball

PHILADELPHIA When you're talking about something as burly as the bass, two is a crowd, and eight enough for any respectable orchestra. What, then, can you expect of five dozen? Deep tones and even deeper meaning, it turns out, for amateurs who showed up Saturday at Verizon Hall to play with the very professional double basses of the Philadelphia Orchestra.

After tunes folk and pop and an excerpt from Beethoven's Symphony No. 9, players said the experience was just this side of a double-bass dream. "It was really cool getting to play with famous people from the Philadelphia Orchestra, because I've watched this orchestra for a long time," said Megan Kenworthy, 12, of Perkasie.

Dubbed a play-in, the BYOB - bring your own bass - was the last in a series of four this season. Woodwind players braved an icy night in February, and two other good-vibe happenings drew nearly a hundred brass players and a small flock of harpists.

The orchestra would like to double the number to eight next season. But a sponsor is needed to cover the estimated $200,000 budget, said orchestra president Allison B. Vulgamore. Musicians initiated the first play-in in 2001, though the format has not been often repeated. Now, Vulgamore says, social outreach is key to reconnecting the orchestra to fans.

"I think what we do off the stage is as important as what we do on the stage. We are at the very beginning of understanding the power of music beyond the concert hall," she said. "All of these events, including our China residency," starting May 21 in Beijing, "are informing the orchestra about opportunities to be fully engaged, not just presenting traditional concerts. Those will always be vital. But these are essential."

Could they also attract new philanthropy? "Possibly," Vulgamore said. As a model for new social applications for music, she points to programs like Carnegie Hall's Lullaby Project, in which musicians help expectant mothers write personalized songs for their babies.

For now, six free orchestra events from May 12 to 15 are meant to deepen bonds beyond the usual ticket-buyer, who can pay up to $230 a pop to hear the orchestra in Salome next week. The free events include a storytelling musical exploration at the Free Library, side-by-side rehearsals with area music programs, a Messiah "sing-in," a lunchtime concert at the Comcast Center, and a May 15 neighborhood concert at the Navy Yard.

With momentum - and funding - the orchestra hopes to grow its sectional play-ins to a full-orchestra play-in. Said Vulgamore: "With enough people, we might need the Wells Fargo Center."