Charmingly and forcefully, Astral Artists has finessed its way onto the local and national arts scene. Twenty years ago, nearly no one saw the need for an organization that would help young talent make the leap from conservatory to stage by giving sage career advice, booking concert dates, and making the kind of connections for an emerging artist otherwise available only by landing a hard-to-get agent.

Now, like the New World Symphony in Miami and Concert Artists Guild in New York, this unlikely wildflower seems indispensable - to audiences as well as artists. In its concert series, the point isn't necessarily musical polish, though there was plenty Saturday night at Astral's 20th-anniversary gala concert at the Perelman Theater. A video of interviews with Astral musicians and founder Vera Wilson revealed its work away from the city's prime venues with the elderly and disabled. When clarinetist Benito Meza said no audience was more important than any other, you believed it.

Astral alumni returned to perform. Pianist Andrius Zlabys showed his unusual insight into Bach, balancing elegant legato with near-pizzicato lightness in the Fantasia and Fugue in A Minor, BWV 904. Soprano Dísella Lárusdóttir delivered two Mozart concert arias with Andrew Hauze leading a small chamber orchestra, her voice pleasant and strong though not yielding deep meaning of the texts.

The Jasper String Quartet and others on the current Astral roster took on the Mendelssohn Octet in E Flat Major, Op. 20. If first violinist J Freivogel raised the idea in the first movement that he couldn't quite conquer the part with the powerful elation it demands, all concern was waved away with his highly detailed work in later movements. This ensemble is just on the edge of being able to take a few more chances.

The concert was part memorial. Julian Rodescu, an integral part of Astral from its founding, died a year ago at 58. He was the dedicatee of Birdsong, for violin and piano, by Vivian Fung. There's something beguiling about remembering someone like Rodescu - a singer with a low resonance so powerful Riccardo Muti described it as a basso profondissimo - with a skittering avian character sketch. But in a way, the piece puts aside the physical manifestation of the man to peer at something else - perhaps the way he tended to be everywhere at once, alighting to mentor a young artist or appearing unexpectedly on a street corner to focus the music critic's attention on an important development. Fung asks violinist Kristin Lee and pianist Conor Hanick - expert, both - to go far beyond the usual techniques, to screech, wail, dash, and operate at speeds from dreamy to moto perpetuo. It came and went like a wind chime caught in a snowstorm, then left to slowly twist in the gentle aftermath.

Rodescu had a hand in the development of the short film Who Stole the Mona Lisa?, which was premiered at the first Philadelphia International Festival of the Arts. In it, pianist Alexandre Moutouzkine provides a piano transcription of Stravinsky's Firebird Suite. It's possible to let attention be dominated by Micah Chambers-Goldberg's witty animation, but to do so is to cheat a major act of compositional creativity. Moutouzkine's work is anything but mere reduction. He evokes orchestral sound, but uses Stravinsky's score as a jumping-off point to make a work so idiomatically of the piano that it becomes a distinct thing in itself. Astral could easily put it out on stage without the film. Even so, on this night, perhaps justly for a group like Astral, music stole the show.