Paul Polivnick has held positions with several orchestras around the country, and at Oberlin Conservatory, and he has nearby ties as well: He directed the New Hampshire Music Festival from 1993 to 2009 and retains a laureate position on its roster. Now a freelance conductor, he was available to take over this week’s Portland Symphony Orchestra concerts when Robert Moody was forced to bow out after his father’s death, a few days ago.

Conductors who take over concerts on short notice often change the programs, but Polivnick left the one Moody planned intact – a classy move, given that two of the four scheduled works, the Barber Violin Concerto and Mason Bates’ “Alternative Energy,” are not pieces conductors perform so often that they’d be at their fingertips. But the Barber was a vehicle for the orchestra’s concertmaster, Charles Dimmick, and Bates, whose music has turned up on the orchestra’s programs before, is known to be one of Moody’s favorites among younger composers.

Polivnick showed himself to be a solid, efficient conductor with some unusual ideas. In his curtain-raiser, Brahms’ “Academic Festival Overture,” for example, the string phrasing toward the start was trim and tight, to the point of sounding clipped. It was hard to know exactly what Polivnick was after – and you inevitably wondered, since the clipped phrasing called attention to itself.

Perhaps his aim, in this atypically high-spirited Brahms score – a potpourri of student drinking songs and other light themes, composed for the ceremony at which the composer received an honorary degree from the University of Breslau – was to peel away the weightiness that has accrued to it over the years.

Coaxing the full orchestra to project the piece with the clarity and transparency you hear in a chamber music performance was certainly one way to accomplish that, and you had to admire the nuance of the orchestra’s performance. But a byproduct was a lack of heft that took some getting used to.

There was a similar lightness in Polivnick’s reading of the Barber Violin Concerto, an attractive, sweetly lyrical 1940 work that seems to move in and out of vogue, without quite attaining the place in the standard canon that it clearly deserves. It could be that violinists have had mixed feelings about Barber, an unapologetic neo-Romantic who composed richly melodic works at a time when most of his colleagues were writing more self-consciously difficult music. If so, that will change as violinists continue to revisit it in a less dogmatic era.

Barber understood the degree to which violinists like to make their instrument sing, and he provided ample opportunity in the first two movements, before turning his attention to daredevil virtuosity – the other quality violinists prize in a concerto – in the perpetual motion finale. Dimmick was entirely at home here. He shaped the solo line beautifully, with a lustrous, carefully regulated vibrato and a focused but flexible tone, and his account of the finale lacked nothing in energy or precision.

Barber also lavished ample attention on the orchestral writing, including some lovely solo passage work – most notably, a plangent oboe passage at the start of the second movement, which Amanda Hardy, the orchestra’s principal oboist, played gracefully. There were moments in the slow movement when the paired trumpets were not fully in sync; but in the finale, the trumpet lines could not have been more tightly entwined.

If you’re looking for splashes of orchestral color – nonstop and constantly changing in both texture and balance – then Bates is your man. His four-movement “Alternative Energy” (2011) is an imaginative, sci-fi meditation on our relationship with energy, starting with Henry Ford’s experiments on the early automobile and moving into the future for a glimpse at a 22nd-century Chinese nuclear plant and, eventually, a post-global warming 23rd-century Reykjavik – now a bird-filled rainforest – where people are trying to build a fire.

It’s a busy piece, packed with detail and nonstop morphing. Bates makes use of the full orchestra’s opulent palette, with an expanded percussion section, as well as electronic sounds (including the finale’s birdsong – in dialogue with the live flutes – and high-tech timbres throughout the piece), and draws lightly but programmatically on music of the past. In the opening “Ford’s Farm, 1896” movement, for example, you hear some rustic fiddling, and later a hint of Gershwinesque bluesiness.

Polivinick drew a powerful reading from the orchestra and closed the program with an energized reading of “Bolero,” Ravel’s slowly unfolding, proto-Minimalist crowd-pleaser.

Allan Kozinn is a former music critic and culture writer for The New York Times who lives in Portland. He can be contacted at:

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