Exciting as it is when superstar musicians alight at local concert halls, the hard-core classical crowd knows of figures just as accomplished and charismatic who live here and give lower-profile concerts often, if not constantly.

Three converged Monday on the American Philosophical Society - to a packed house - exploring repertoire that superstars can't risk with the responsibility that comes with their high fees. Presented by the Philadelphia Chamber Music Society, the evening also had a performance of Brahms' Clarinet Sonata (Op. 120, No. 1) that was the most arresting I've encountered.

Built around the Philadelphia Orchestra's beloved principal clarinetist Ricardo Morales, the recital also included associate principal cellist Efe Baltacigil and Chinese-born, Curtis Institute-trained pianist Natalie Zhu. Given the limitations of the clarinet repertoire, the composer lineup contained unknown names, though the evening never courted obscurity. Minor or major, the composers inspired engrossing performances.

In fact, the program's most shamelessly derivative piece, a clarinet sonata by Argentina-based Carlos Guastavino that's more or less Latinized Rachmaninoff, prompted some of Morales' most spellbinding playing, with fine shadings of tone and a poetic way of giving each succeeding theme an entrance of sorts, usually with an intense decrescendo that heightened the listener's expectations.

Time Pieces (Op. 43) by Chicago-born, Tucson-based Robert Muczynski was a significant discovery; its harmonic sophistication juxtaposed against lyric simplicity suggested avant-garde folk music. In contrast, Beethoven's Clarinet Trio (Op. 11) is actually more uneven, though the cello-dominated second movement showcased Baltacigil in ways that made it worth his while.

Zhu plays in great concert halls as the recital partner of Hilary Hahn, but is usually more interesting elsewhere. A prime instance was the Brahms sonata. Given its chronologically advanced opus number, the piece is usually about the serene resignation of old age. Not with Zhu. The piano's first-movement entrance was so fierce as to be almost unrecognizable, convincingly so. The piece became a rebellion at the gates of mortality.

Musical rapport can take many forms, and here, the potential balance problems of such a full-out pianistic approach - the lid was open at full stick - didn't exist. The music-making was seamless enough that Morales and Zhu effectively finished each other's Brahmsian sentences and delivered emotional echoes to the other's grand flourishes.

Contact music critic David Patrick Stearns at dstearns@phillynews.com. Read his recent work at http://go.philly.com/ davidpatrickstearns.

Ricardo Morales returns to the Philadelphia Chamber Music Society in a concert with the Kalichstein-Laredo-Robinson Trio March 4 at the Independence Seaport Museum. Information: 215-569-8080 or www.pcmsconcerts.org.