BEAVERTON–Not that I’d outlaw the scruffy looks of most performing Portland jazz musicians, but a change-up is welcome when an East Coast group such as the Aaron Diehl Trio comes to town. Dressed in coats and ties, Diehl’s starched white cuffs gleaming like the piano keys, the trio performed coolly Jan. 19 in front of plush velour curtains turned deep blue by lighting at the 550-seat Reser Center in Beaverton. The house wasn’t sold out, but 400 were listening, and the hall’s Douglas fir wood contributed to the warm, full-toned sound.

Led seamlessly and quietly by pianist/composer Diehl, the trio and its precisely laid-down technique were as elegant as its mid-afternoon presentation at Friends of Chamber Music’s “Beyond Classic Series.” The lion’s share of the Friends’ audience is classical music fans (only two other jazz concerts – the Harlem Quartet in 2024 and the MJ New Quartet in 2022 – have been part of the recent programming), but Diehl’s group, all of whom studied at Juilliard, had the crossover acumen to snow the audience with a variety of little known jazz compositions, some not at all familiar unless you’re already a Diehl fan. He played a couple of his own compositions, including one that he wrote in 2013 for a Museum of Modern Art concert. His mission was to choose an artwork to inspire his piece, and his pick was Piet Mondrian’s frenetic and colorful 1943 “Broadway Boogie Woogie,” painted when Mondrian settled in New York City during World War II.

Not only can Diehl switch from Bach to boogie with no problem (though Bach was not in the repertoire this time), but he likes to follow in the vibe of Errol Garner, Jelly Roll Morton, and Ahmad Jamal, all of them quietly tuned-in musicians focused more on spareness than on theatrics. I’d add Bill Evans to those influences.

Diehl’s final composition, “Stella’s Groove,” was written for his mother, a former Olympic high jumper (though Diehl didn’t mention that), and the lively swinging tune proved what Thelonius Monk said about jazz piano: “The piano ain’t got no wrong notes.” Diehl played just about every note (not only on this tune) of the Reser’s beautiful Steinway grand piano, throwing in an abundance of glissandos.

It’s commonplace to hear Monk, Wayne Shorter and Antonio Carlos Jobim chestnuts at jazz concerts, but it’s more fun to hear the less played pieces of these towering mid-20th century composers. That’s just what Diehl’s group did for an uninterrupted 75 minutes. Instead of Shorter’s “Footprints,” we heard “Mikayo”; instead of Monk’s “Straight, No Chaser” or “‘Round Midnight” we got an earful of “Monk’s Mood.” And the piece by Jobim, the king of bossa nova? The trio played the rather serious “Passarim,” which brought attention to the plight of the South American rainforests in the late ’80s.

Diehl knows his jazz history as well as the art of engaging an audience. His soft-spoken explanations, as subtle as his piano-playing, were a delightful addition. With some tunes I’ve never heard before, the explanations were more than welcome. Most exciting were several pieces from Sir Roland Hanna’s 1977 24 Preludes. Though American, Hanna earned the “Sir” from the president of Liberia after playing concerts to help raise money for education in that African country.

Another lesser known piece was “Sun Out” from Lucky Thompson’s 1973 album, I Offer You, which the musicians saved for the last part of the show.

Because jazz is built on improvisation, often musicians are determined to play like magicians possessed to show off their virtuosity and originality. They expect audiences to simply get it. Case closed. At a 2023 PDX Jazz Festival concert with NEA Jazz Master/extraordinary bassist Dave Holland, guitarist Kevin Eubanks and drummer Eric Harland–all excellent musicians–Holland said, “We’re gonna just do what we do. Enjoy the journey.” The forget-contextualizing method is one way to play jazz for a diverse audience, but I prefer Diehl’s approach.

Diehl’s sidemen, bassist David Wong and drummer Aaron Kimmel, played at the right temperature for Diehl, who is not a key-banger, but who can run tirelessly up and down scales and change dynamics to keep things pulsing and opening up. These “side” guys are music professors, Juilliard grads and regulars at New York jazz clubs, playing with such biggies as pianist Benny Green, the Vanguard Jazz Orchestra and trumpeter Terell Stafford. Wong, whose work ethic is resolute, according to Diehl, used a bow a good part of the time, despite the agility of his long fingers. Both musicians had several solos, but the gig was Diehl’s, and Wong and Kimmel helped to make him sound really good.

A small disruption occurred when several people, at three different times, tried to stop an audience member from recording the first part of the concert. “No recording” was announced as usual pre-concert, but this person had been given permission by the authorities to record, and she continued despite the protests. It would help in the future if those kinds of potentially disruptive issues were announced pre-concert to cut out the kerfuffle during the performance.

Otherwise, it was a very good show, a felicitous combination of old-school and contemporary sensibilities, and a precursor to what I hope will be more jazz concerts from Friends of Chamber Music.