If you had hoped to hear greater liberation from the written note in Emanuel Ax's handling of his encore, Chopin's Nocturne in F Sharp, it was not to be found. A full sense of terror never emerged in the last movement of Chopin's Piano Sonata in B Minor.

Courting danger is not who Ax is. Everything sounded so easy for the pianist, widely considered one of the greats, at his Philadelphia Chamber Music Society recital Wednesday night at the Perelman Theater (though I doubt it could have been easy at all). I kept listening for layers of meaning, an opinion ventured on some long-overlooked emotional truth. Ax is always smooth and facile -- jaw-droppingly so -- but he tends toward the conservative when it comes to drama.

One could certainly be perfectly happy with the artist he is, even overjoyed at times. The recital was constructed around Schubert as well as Chopin, its most tantalizing connective tissue coming by way of a new piece by Samuel Adams, the 31-year-old son of elder statesman composer John Adams. Impromptu No. 2: After Schubert has the virtue of nearly constant motion, a hopeful gurgling, and some of the same kind of rushing, repeated figures you hear in Schubert, but in a modern and highly original idiom.

The technique it used was right up Ax's alley. The pianist has a way with fast runs, playing through them with the inevitability of a fast zipper. The third of Schubert's Four Impromptus, D. 935, the one in B flat that starts so innocently, was filled with technical feats and no small amount of subtle elegance. The heart leapt in the final variation at the lightness with which Ax rendered the quickest runs. They were as silver flashing in sunlight.

In four Impromptus of Chopin, he was, again, restrained. But he flexed the tempo a fair amount in the first movement of Chopin's B Minor Sonata. Sometimes the critic gets a particular interpretation lodged in his mind's ear, and, I must admit, I don't think anyone ever understood this music the way Martha Argerich did. She heard, in the outer two movements, all the fire and magic of Liszt and Berlioz. Ax, for all of his thought and lovely sound quality, seemed to want to tame it. The truth of this music waits in a place of greater horror than he wanted to go.

The next guest in the PCMS piano recital series is Rudolf Buchbinder on April 26 in an all-Beethoven program at the Perelman, Broad and Spruce Streets. www.pcmsconcerts.org, 215-569-8080.