JERUSALEM – Ariel Lanyi sits on a pillow to reach his piano and needs to stand on a chair to play the double bass. He peeks over the rims of the drum set and isn’t big enough to use a full-sized violin.

The piano is the 9-year-old Israeli prodigy’s favorite instrument, but when he gets going at a jam session, he can’t stick to just one, playing each with dexterity well beyond his years.

The classically trained whiz kid has already recorded a jazz album and is now the youngest member of the Kadima Collective, a leading avant-garde jazz troupe in Israel.

Ariel began playing his family’s piano at 2. By the time he had his first formal lesson, two years later, he could already play a Bach prelude. At 7, he discovered jazz.

He said he knows he’s different from other children, but that’s a good thing.

“I’m special – unique,” he said.

On a recent weekend, Ariel stayed up past his 9 p.m. bedtime to perform a free-form jazz concert in a small bar in Jerusalem.

His gray-haired teacher, Jean Claude “J.C.” Jones, squeezed rhythms from every part of the bass during the performance, while the dimpled, blue-eyed protege replied on the violin.

“The music is completely mature and exceptionally developed,” wrote local jazz critic Adam Baruch on his blog at jazzis.com. “It’s almost scary to imagine what this kid will be up to in a few years.”

The high pressure of the classical music world can be cruel to children and cause young geniuses to burn out. That’s why Gabriel Lanyi is pleased his son has chosen jazz.

“The people in jazz are so laid-back,” he said. “There’s really no pressure here, and that’s good for Ariel.”

While surfing the Internet at age 7, Ariel accidentally clicked on a link to the great jazz pianist Earl Hines. He couldn’t get enough.

“Within months of hearing jazz, he was an expert because he downloaded hundreds of songs,” his father said. “He lives half his life on the Internet.”

When it comes to music, Ariel has no inhibitions. During a jam session, he’ll reach over and pluck the strings of Jones’ bass. During a concert, he’ll stomp the stage and play a jig on the violin while performing an Irish step dance.

“Not only do I want to be a classical pianist and jazz pianist and a composer,” Ariel said. “I’ve decided I also want to be a musical comedian.”

His family wants him to have a normal childhood. In his spare time, he takes judo and swimming lessons. He also has a regular study schedule, though he gets Wednesdays off from elementary school to take special music classes at the prestigious Jerusalem Academy of Music and Dance.

And like many young musicians, he doesn’t always like to practice.

“I could practice half an hour; I could practice two hours – I don’t care” he said. “I care how well I practice, not how much.”

Still, Ariel is anything but normal as a musician. At 8, he recorded a jazz album, “31 Bars,” which includes several original compositions.

He also speaks fluent Hebrew, English and Russian, his parents’ native language.

Lea Sarni, principal at Ariel’s school, said the third-grader is a good student who gets along with his classmates and works hard. “We’re all very proud of Ariel,” she said. “Maybe he’ll be famous one day, and I will be very proud to say he was my student.”

Jones, who doesn’t usually teach children, said he didn’t know whether Ariel would become a great jazz pianist, but he was certain he would be “big in music” in some form.

“He’s tough. He knows what he wants,” Jones said. “That’s good in music.”