What is that strange new piano at Philly’s Kimmel Center, and why is it here?

From one angle, the newest musical instrument at the Kimmel Center looks like a classic grand piano — big, sleek, and glossy black. But then you look down at the keys and sense that something is amiss. The keyboard is curved, its keys oriented ever-so-slightly toward the pianist’s hands.

This is no ordinary grand piano.

The instrument arrived at the Kimmel last week as a bittersweet postscript. It was designed by Rafael Viñoly, the architect who died in March, and now it has been united with the arts center he designed a quarter century ago.

Viñoly had spent years developing the piano with the hope that it would be adopted as a more ergonomic alternative to the traditional keyboard. A trained pianist himself, he owned and played six instruments, including two he kept in a special acoustically-isolated practice room in his New York office. After the esteemed architect’s death, his son, Román, began to consider how to extend interest in the unusual instrument, and Philadelphia beckoned.

“I realized it makes the most sense to put it where great artists go to play, a place designed for people to go and spend time with an instrument and choose it for a performance.”

He also wanted it close to a school, and the Curtis Institute of Music was just a few blocks away. Plus, with the Philadelphia Orchestra and Kimmel now being run by an old family friend, Matías Tarnopolsky, “it just seemed like a cosmic alignment of things,” said Román Viñoly.

The idea for an alternative piano design emerged at a 2016 dinner party at Daniel Barenboim’s house in Berlin. Rafael Viñoly was there, as was Martha Argerich, “and they were talking about the specific physiological challenges of being a pianist,” said Román Viñoly. “And Barenboim, who is small in stature and has quite small hands, talked about the challenges that he faces when he sits in front of a modern keyboard, and my father in that instant asked, ‘Why isn’t the keyboard curved?’ He said to them, ‘Wouldn’t it be great if we did that?’ And they very flippantly said, ‘Yeah, sure, try it.’”

Viñoly worked with Belgian piano maker Chris Maene to produce an instrument, and, after several years of development and trials, pianist Kirill Gerstein was the first to play it in public — at the Verbier Festival last summer.

There’s another unusual aspect to the Maene-Viñoly Concert Grand: It is straight-strung rather than cross-strung, which means unlike most modern pianos, the strings in the body are perpendicular to the keyboard and don’t overlap with each other. That construction — which some pianists say makes the colors of different registers more distinctive — was the element that most intrigued Philadelphia pianist Jonathan Biss when he stopped by recently to try out the instrument.

“It’s a fundamentally different way of building a piano,” said Biss, who is co-artistic director of Marlboro Music. “I was immediately struck by the warmth of sound in the middle-upper register, and the bass was full without being overpowering.”

Biss emphasized that hearing the piano in a low-ceiling room (it’s currently in an education space on the Kimmel’s second tier) was limiting in terms of assessing it, but he said the sound was “effortlessly powerful without being harsh.”

As for the curved keyboard, where, the theory goes, the farther keys are easier to handle because of being angled, Biss said: “I have very long arms, so that was not necessarily such an issue for me, but there are pianists whose wingspan is significantly shorter than mine for whom this might make a difference.”

He also feels that “the existence of high-quality instruments that are not all like one another is a really good thing. You read accounts of performers in the late 1700s and first half of the 19th century, and they had preferences for different kinds of pianos from country to country. There was a lot of variety even from maker to maker.”

The development of a piano with different sonic possibilities “strikes me as a very positive thing for pianists and for music,” said Biss.

That highlights the reason for having the piano at the Kimmel — to give artists another option.

“We’re excited for people to try it,” says Tarnopolsky. “And if some of the great artists coming through like it and want to use it with the orchestra, we’d be thrilled.”

No one has committed to performing in public on it yet. The instrument’s residency is currently open-ended, says Viñoly, giving a stream of pianists a chance to get to know it. It is one of three Maene-Viñoly Concert Grands in the world, with a fourth on the way.

“It’s an especially meaningful project for me. Because obviously my father was known for his architecture, but his passion in life was music,” said Viñoly. “And for him to have been able to make a contribution to professional pianists, for him to have been able to contribute something that enhances their artistry, I think would have been his proudest achievement.”