What: Central Oregon Symphony Fall Concert

When: 7:30 p.m. Saturday and Monday, 2 p.m. Sunday

Where: Bend High School Auditorium, 230 NE Sixth St.

Cost: Free, but ticket required; available in advance at area bookstores — Roundabout Books, Dudley’s BookShop Cafe, COCC Bookstore (Bend); Paulina Springs Books (Sisters); Herringbone Books (Redmond); Sunriver Books and Music

Contact: cosymphony.com

Don’t be fooled by the fact that Central Oregon Symphony’s Fall Concert, its first of the 2019-20 season, has “just” two pieces.

In performance Saturday through Monday at Bend High School, “This particular concert, because of the works that we’re playing, there are only two pieces, Maestro Michael Gesme said. “But each one of those things is four movements long, three movements long, so the reality is there are seven pieces.”

The first of the two pieces is Johannes Brahms’ Piano Concerto No. 1, featuring Brazilian-born pianist Ednaldo Borba, who received his Ph.D. in piano performance last year from the University of Oregon. When mapping out each season, Gesme usually asks soloists what they might like to play with the orchestra, and when Borba suggested Piano Concerto No. 1, Gesme leapt at the chance.

The concert weekend marks their first time working together, but Gesme has seen Borba play.

“He’s just phenomenal,” Gesme gushed. “I’m super excited to work with him.”

Piano Concerto No. 1 clocks in at 50-some-odd minutes, but with those distinct movements Gesme mentioned, it scarcely comes off as monotonous.

In the 1850s, when the concerto debuted, “Brahms is a relatively young dude. He’s a great pianist, so he’s going to premiere this piece,” Gesme said. “(He’s) already got a name, and so everything he does is kind of put under the microscope.”

Brahms famously labored over it for a while, and at one point is was a piano duet, Gesme said.

Unsatisfied, Brahms decided to throw the orchestra in as well. Now it was in concerto territory, which Gesme helpfully explained as being “basically where you have a solo instrument, and the orchestra providing the accompaniment, for lack of a better term.”

The form was well established by the Romantic Period, when Brahms had to go and tinker with it.

“Symphonic music had been around for a couple of hundred years at this point and already had a well-developed sense of orchestration and how things worked and what can be done with an orchestra to create beautiful sounds,” Gesme said. “Up until that era … concertos were all about the soloist. The orchestra was merely ‘boom chick chick’ in the background while they (the soloist) were doing all of their pyrotechnics. They were designed as a feature for the hot-ticket soloists of the day, which were often the composers.”

With Piano Concerto No. 1, Brahms set expectation on its ear. Not only did the orchestra play a more prominent role, but at times the hot-ticket soloist provides the accompaniment to the orchestra.

“There are beautiful sections where the orchestra gets to shine, and the pianist is either an equal partner, or … sometimes the pianist is the one that’s providing just the accompaniment while we have this gorgeous flute solo going on, or this really beautiful bassoon solo.”

All of which makes for a lovely concerto experience, but as you can probably guess, flouting a couple of centuries of convention did not exactly go over with audiences back in Brahms’ day.

“It wasn’t super-well received on the get-go,” Gesme said. Audiences actually hissed at the premiere performances. “People were just not expecting what they got. … I’m sure Brahms was devastated.”

Be warned: It’s heavy, Gesme said. “It’s Romantic heavy. And I mean ‘heavy’ in the dark chocolate, amazing — whatever you view in terms of, like, you put yourself through the wringer when you go through a Romantic juggernaut.”

The back half of the concert, made up of Austrian composer Joseph Haydn’s last symphony, is the complete opposite of heavy.

“(Haydn) is the epitome of the classical model,” Gesme said. “He can spin a good tune like nobody’s business.”

And he can bait and switch: Symphony No. 104’s early measures suggest a somber affair ahead.

“You think, ‘This is going to be very serious,’ and then, he says, ‘No.’ This is just pure joy … movement after movement after movement,” Gesme said. “It’s a really lovely foil for the Brahms.”

Somewhat confusingly, Haydn wrote 12 symphonies during his two late-career trips to London, collectively known as his London Symphonies. But when someone references “the London Symphony,” they’re referring to No. 104, the last of them.

Whatever you call the piece, the community orchestra is very well-positioned to play it given current talent levels, Gesme said.

“It’s the combination of the right group of people to play this music. I’ve got this perfect combination right now to do an amazing job with this symphony, and they play it so well.”