NORTH BETHESDA, Md. - New concertos pop up so frequently that composers worry that they're turning into concerto machines.

The venerable Elliott Carter is up to 11, the reliable Ellen Taaffe Zwilich has written eight, and Jennifer Higdon has followed up her breakthrough Concerto for Orchestra with seven more works in that medium, most recently a Violin Concerto that has had so many performances that abundance of supply clearly hasn't lessened demand.

The piece's East Coast premiere Saturday with the Baltimore Symphony Orchestra under Marin Alsop followed its February premiere by the Indianapolis Symphony Orchestra, as well as performances in Toronto; Lucerne, Switzerland; and Liverpool, England, where Hilary Hahn (for whom the piece was written) recorded the concerto for Deutsche Grammophon.

The Curtis Institute of Music (where Higdon is on the faculty and Hahn an alumna) is one of four co-commissioners - its street address, 1726, is the first movement's subtitle - which means Philadelphia will hear it in the next year or so along, with Dallas, Detroit, and Nashville.

The Saturday performance at the Music Center at Strathmore - a newish acoustical jewel located just beyond the Washington Beltway - was an extremely happy occasion.

The orchestra played with comprehension and confidence under music director Alsop (whose contract was just renewed for five years, through 2015), not just in the Higdon concerto but also in a smartly rendered Dvorak Symphony No. 5.

Hahn was completely on top of the concerto, and though it's often hard to tell when this ultra-serious musician is having a good time, she was definitely enjoying herself. The audience was so receptive that in a post-concert talk-back session Alsop looked out over the well-filled hall and joked that more people stayed than attended the concert.

Typically, new concertos clock in at less than 25 minutes in order not to crowd the Beethoven overture on one end and the Brahms symphony on the other. But Hahn asked Higdon for "a major work," which translated into 37 resourcefully sustained minutes. The first movement begins distinctively with lightly colored violin harmonics sounding at all different parts of the solo instrument's range. The effect is like colored lights flashing out of darkness with playful, peekaboo randomness. From there, the concerto is full of the lyricism and heroism that's an essential part of the genre, with much emphasis on what one might call Hahn's "Kreisler zone" - a rich lower-string tone reminiscent of the great Fritz Kreisler.

The concerto's themes run the gauntlet through tight, seesawing orchestral harmonies that continue to emerge, from piece to piece, as an increasingly characteristic aspect of Higdon's compositional voice. Few big-scale concertos have so much interplay between violin soloist and the orchestra's concertmaster, who joins the soloist in some full-fledged duets - ones that Higdon later said were inspired by Indianapolis concertmaster Zachary DePue, another ex-Higdon student from Curtis and also part of the Time for Three string trio.

The second movement showed Higdon moving toward compositional prescriptions: The music is wrapped around repeating chord patterns, chaconne-style, though so seamlessly and with her usual intuitive lyricism that the work's formality registered itself mostly subliminally. You're not sure why the movement leads you along, but it does.

The third movement is one of those curious cases of a composer rewriting history, as Andre Previn did in his Violin Concerto, which, intentionally or not, appears to recast the Korngold Violin Concerto with a superior sense of thematic development. Similarly, Higdon seems to be shoring up the Barber Violin Concerto's weak link - its third movement, which fulfills the traditional virtuoso side of the concerto more out of duty than inspiration. Alike in concept and manner, Higdon's third movement has much more stuffing and a more prolonged air of purpose.

Higdon admitted in the post-concert talk that Barber was the primary inspiration for her Violin Concerto. Amid all of that, one listener observed the unusual gender solidarity of the project (Alsop seemed only then to notice it), and wondered if that aided the Hahn/Alsop/Higdon working relationship. Hahn piped up, "I feel it's really different working with short-haired people."

Might there be more to that than she thinks? What would Stoky say?