François Lindemann, founder and member of the Swiss Piano Seven, likes to say the sound of seven pianos is "not seven times the power of one piano," hinting that while a big sound is to be expected, there's so much more by way of layering, juxtaposition, ensemble and individual flair. But however one describes it -- dramatic, unpredictable, bold, sometimes romantic -- the concept is undeniably unique, unlike anything else in contemporary classical music.

Lindemann and company, including two guest musicians (violinist Stéphanie Décaille and percussionist Nicolas Levon Maret), bring their one-of-a-kind sound and original music to the National Center for the Performing Arts for a 7:30 pm performance tonight.

In 1986, Lindemann and longtime friend Sebastian Santa Maria were touring Europe in a piano duet when they decided to try an experiment. They called up five of their pianist friends and organized a concert in Lausanne, Switzerland, which was received with such anticipation that a 700-seat venue was filled beyond capacity on the evening of the performance, with 400 people turned away at the door. After a successful second concert one year later, Piano Seven was well on its way toward becoming an international mainstay, with 10 CDs to follow and tours around Europe, Asia (including China three times), the Middle East and South America.

Piano Seven has evolved since its inception, with only Lindemann and Michel Bastet remaining from the original cast. Santa Maria passed away in 1996 of a rare metabolic disorder, a loss that "affected me particularly," Lindemann says. "It affects me when I speak of him now." But the group has persisted. We spoke with Lindemann recently about Piano Seven and tonight's concert.

What kinds of songs are in your program?
We have different types. We have romantic melodies, also more rhythmically written pieces, and pieces influenced by Latin music, and tango music from South America, (songs) influenced by classical European composers...

(Four years ago, we began adding guest musicians) to have a different flavor, and maybe because I was thinking that having only the sounds of the seven pianos for one and a half hours would be a little bit boring.

We have some effects when we prepare the piano, which means we can put some Scotch tape over the strings or some pins on it to dampen the sound a little bit; cloth on the strings so we can mimic the sound of the pizzicato of a violin. We have one song like that.

Have you guys changed over the years?
Of course. Time makes us more confident, also sometimes more anxious. It depends. And musically, we "grew up" because of the young people (who have replaced some old members). They tell us about the electro, about the rap, about the rock -- and we talk to them about jazz, so it's a real exchange. It's very important to share our experiences.

What was Santa Maria like?
He was quite well known in our city and South America, and France because he did arrangements and composing for pop singers in Paris.

I wrote a song for him, which I played when we did a tribute to him a year after his death. I asked people around France and Switzerland to make a tribute to him at a kind of an open-air festival, and it was emotionally very strong to have all these friends playing for him.

All of us learned a lot from him, from his playing, from his way of life. He was very open and open-minded.

What should people expect from your concert?
People have to come and be empty of any preconceptions. Just be open to listen to music without stickers: it's not jazz, it's not classical, it's not Western music, it's not folk music -- it's just music from seven writers, seven composers, seven pianists. We experiment, we use noises from what we hear from the streets, from our life. And this is the music we play.

Piano Seven plays at the NCPA Concert Hall tonight at 7:30 pm. Tickets can be purchased at Piao.com.cn.