For its second of four programs this season, on Sunday the Portland Chamber Music Festival offered three masterpieces from as many centuries in performances invariably solid and often downright thrilling.

The opener, which could easily have been a closer, Mendelssohn’s String Quintet No. 2 in B-flat Major, op. 87 (a posthumously published 1844 composition) provided thrills. Not heard nearly often enough, it blends high-level inspiration with Mendelssohn’s impeccable ear for string tone color and his uncanny instinct for formal balance in the midst of Romantic effusion. For this “viola” quintet (rather than a “cello” quintet), the ensemble arrayed themselves classically, with violins Anna Lim and Gabriela Diaz facing violists Jessica Meyer and Melissa Reardon, leaving cellist Trevor Handy in the middle. They opened with vim and passion, a luscious blended sonority, handsomely shaped phrasing and superb dynamic variety and control. In the build to the recapitulation, Lim deployed perfectly calibrated tension. The second movement, curiously labeled “adagio scherzando,” cuts against form for the composer noted for brilliant elfin scherzi: this is a gentle intermezzo, whose texture is kept lively with little descants. The playing, graceful and sure-footed, fully inhabited the music. The slow movement’s gentle and regular opening soon gave way to un-Mendelssohnian anxiety; Handy was particularly convincing in the obsessive rhythmic kernel of this section, while Lim sang sweetly in the outer sections. The finale, by turns springy and lyrical, once again brought forth fish-shoal ensemble closeness and dexterity that left nothing to be desired.

The first half ended, somewhat daringly, with Benjamin Fingland, clarinet, performing Synchronisms No. 12 (2006) by old-master modernist Mario Davidovsky. His series of works for acoustic instruments and electronics (still somewhat anachronistically called “tape”) begun in the 1960s (one of the series is choral and one orchestral), explores the ways in which live and generated sounds can work together in a manner typical of traditional chamber music. Fingland has worked closely with the composer, and in this brief piece he showed masterly fluidity, phrasing and technical agility (not everyone can tongue-slap so effectively). The electronic part, consisting of both synthesized (and rather ‘60s-sounding) sounds and extensions of actual clarinet tones, sounded remarkably subdued and deferential, disclosing a highly intelligible structure. It cuts off abruptly as a new idea starts taking shape—an amusing if somewhat frustrating esthetic choice.

The concert needed an even more dramatic closer after the full-blooded Mendelssohn opener; Elgar’s Piano Quintet in A Minor, op. 84 (1917), made a good choice. Elgar, like Mendelssohn, produced a quintet after a period of rustication; but Elgar’s retains a dark aura, lightened only by the generally upbeat finale.

Abetted by the centenary of World War I, in whose shadow Elgar’s late work must be viewed, it has received more attention than hitherto (at least in the US, where Elgar remains an acquired taste), especially in the last few years, leading up to its centenary this year. It’s therefore not necessary to go into much detail about the piece itself, other than to note my continuing dissent from the view that the second subject of the first movement has much, if anything, to do with Spanish monks turned into trees.

Henry Kramer, piano; violinists Diaz and Jennifer Elowitch; violist Reardon, and cellist Brant Taylor, produced a fine interpretation. Kramer started with splendidly haunted diffidence, picked up just a little too assertively by the strings. Taylor’s solos in this movement were mesmerizing. Overall, the ensemble stressed the composer’s episodic writing, building up steam only in the Viennese elaboration of the “Spanish” theme and in the vigorous Brahmsian development. We concur with the broad admiration for the central slow movement’s quintessentially Elgaresque melody, introduced affectingly by Reardon. Diaz and Taylor were similarly moving in the rueful middle section. The players admirably brought off the finale’s subtle tentativeness, conveying how its triumphal affirmations are undercut by returning earlier material. The excellent pacing achieved blood-stirring cumulative force.

Vance R. Koven studied music at Queens College and New England Conservatory, and law at Harvard. A composer and practicing attorney, he was for many years the chairman of Dinosaur Annex Music Ensemble.