Tuesday night's Nuance concert began exactly the way it should, with a pair of works that demonstrated the elegance and skill of the Pittsburgh Symphony Chamber Orchestra musicians at the JCC's Katz Performing Arts Center.

Boccherini's Symphony No. 25 was a delectable trifle, taking full advantage of odd little solo combinations. It would be a play within a play if it were a theater piece, but as a musical composition, it immediately tapped the collective brio that is the hallmark of this series.

Patricia Prattis Jennings, the PSO's veteran keyboardist, took the spotlight with Bach's first clavier concerto. It is a piece that can be performed on harpsichord or clavichord, but Prattis Jennings chose the more contemporary piano, where this timeless piece still tested the even-handed virtuosity of her technique.

But if the first half was more black and white, the second half emerged with what might be termed the technicolor side of music. Carnegie Mellon University composer Leonardo Balada's premiere, Caprichos No. 3 for Violin and Chamber Orchestra, provided the primary interest on this program. PSO concertmaster Andres Cardenes, who has championed Balada's work before, served as the soloist, with Larry Loh taking over the conducting reins.

Balada's recent and highly successful sojourns into combining folk and abstract music techniques were evident here. But Balada chose an unusual inspiration for his piece: melodies sung by the International Brigades during the Spanish Civil War.

The German and Irish ballads were more reflective, framed by three Spanish melodies. The first ballad, composed in a German concentration camp, featured Cardenes resolutely climbing out of a pool of sound that faded at the end into a wisp, much like memories that could not be forgotten. The Irish ballad, based on "The Bantry Girl's Lament," featured its song almost whole, with the strings bending like sighs underneath to better effect.

The Spanish trio of songs formed the rhythmic underpinning, like the passion and fervor to be found in times of revolutionary spirit. Here Balada set up a landscape of challenges for Cardenes, with skittering runs and bold double stops over a metric minefield.

It was a piece that often seemed fraught with the confusion of war, where things were musically deconstructed or blown apart. But Balada, teetering on the edge of sanity as the piece progressed, ended with a clever "Jota," in which the spirit of the piece, unlike the soldiers themselves, emerged victorious.

Respighi's "The Birds," nimbly conducted by Cardenes, was like a cleansing breeze after Balada's storm of intensity. This piece brought a smile to the face as it took flight with a raft of deft musical imitations.