• PHOTO BY JOSH SAUNDERS
• Pianist and singer Ariel Pocock performed in Hatch Hall on Friday night.

At Kilbourn Hall Friday night, 4 By Monk By 4 was something akin to a Thelonious Monk symphony, or at the very least, a Monk piano sonata. Because the great jazz composer's tunes have a lot in common with each other -- notably off-kilter timing and dissonant melodic twists -- an hour of nothing but Monk tunes was wonderfully cohesive.

Over 16 years and countless concerts at the Jazz Festival, it's a safe bet that no jazz composer has been played as much as Monk. That's as it should be; of all the genre's great composers, Monk stands alone as the most original and prolific.

The four featured performers Friday night took the stage in various configurations, from solo to duos, culminating in all four on the stage swapping piano benches at the two Steinways in a kind of Monk relay race.

Each of the four pianists brought a different interpretive style to the stage. Cyrus Chestnut, the first to appear, was the most physical and in that way the most like Monk himself. Chestnut always seemed to be reaching over the entire keyboard to find the right series of notes. At times his right hand seemed to be scurrying down the keys chasing his left hand only to be thrown back to catch a chord at the other end.

George Cables was the most ornamental. Every tune he played was decorated by an ornate filigree of notes. Benny Green was the opposite, more spare in his playing than the others. And Kenny Barron played Monk with a decisive touch and the assurance and expertise of the veteran player that he is. "Ask Me Now," "Bye-Ya," "Green Chimneys," "Ruby, My Dear" -- the brilliant tunes, played brilliantly, just kept flowing from the stage.

Benny Green plays Saturday, 5:45 p.m. and 7:45 p.m., in Hatch Hall. $30 or a Club Pass. bennygreenmusic.com.

At Xerox Auditorium, Tessa Souter was winning over the crowd with her excellent band. For most of her set, she took jazz classics, highly familiar in their instrumental versions, and sang them with lyrics she (or occasionally someone else) wrote. Her words to tunes like John Coltrane's "Equinox" and Freddie Hubbard's "Little Sunflower" fit like a glove. And she didn't restrict herself to jazz composers. One of the best songs of the night was a collaboration between Souter and Chopin.

"I wrote these lyrics," she said. "He doesn't mind." He shouldn't; her words to his Prelude in E minor, re-titled "Beyond the Blue," are a perfect fit. And I'm sure he would be proud to have written a tune that sounds like an absolute classic jazz standard. And speaking of unlikely standards, Souter's rendition of Cream's "White Room" recast it as a medieval English traditional song.

Souter's band was exceptional, with the great guitarist Yotam Silberstein, the most melodic bassist I've heard at the festival, Yasushi Nakamura, and the superb drummer, Billy Drummond.

Souter plays again Saturday, 6:45 p.m. and 8:45 p.m., at Christ Church. $30 or a Club Pass. tessasouter.com.

Ariel Pocock had a nicely textured voice with attitude at Hatch Hall. If that sounds unusual it's because Hatch is usually reserved for solo piano, with mics only used for announcing tunes. Pocock played a few instrumentals, but she mostly sang and played well-chosen tunes like Randy Newman's "Living Without You" and Hoagy Carmichael's "I Get Along Without You Very Well."

You can find Ariel Pocock's music at arielpocock.com.

Saturday night, I'll begin with guitarist Matthew Stevens at the Wilder Room. Then I'll hear pianist Benny Green at Hatch Hall. I'll close out the festival with saxophonist Donny McCaslin at Xerox Auditorium.