He Started at the Top, Worked His Way Down : Music: When former soprano Matti Salminen was 17, he had a brief role with an amateur ensemble. That’s when the self-described ‘basso cantante’ decided on classical over pop.

Like many basses, Matti Salminen began as a boy soprano.

“I was one of the highest sopranos--until I was 13,” Salminen said recently in an interview at the Finnish consulate general’s house. “The voice change didn’t shock me. It happened very fast, in a few weeks, three or four. I noticed I was in the middle of something different, which I didn’t understand.

“But very soon I also noticed this was something I could use. So it wasn’t a shock, and I never thought of leaving music.”

In fact, Salminen, who sings excerpts from Mussorgsky’s “Boris Godunov” tonight through Sunday with fellow Finn Esa-Pekka Salonen conducting the Los Angeles Philharmonic, was destined not to stop until he had reached the most velvety-rich lower vocal depths.

He calls himself a “basso cantante” and says they’re a rare breed. “They used to talk about the scarcity of tenors,” Salminen said, speaking through a translator. “The lack of bass singers is just as serious--at a certain level, which we are talking about. You’ll find many more bass-baritones.”

Salminen was born in Turku, Finland, in 1945. He grew up “in a normal family, in the sense there was music, but my parents were not makers of music although they participated in choir,” he said.

His mother took him to a children’s chorus, and the director spotted his talent. After his voice changed, the same teacher took him to study with the famous Finnish coloratura soprano Lea Piltti at the Finnish Opera in Helsinki. He was 15 and undecided whether to pursue serious or popular music.

“I earned money for my studies by singing for entertainment,” he said. “At that point I knew I would be a singer, but I hadn’t decided which field--classical or pop, like Frank Sinatra, not Rod Stewart.”

The decisive moment came when he was 17 and singing his first role--”a nasty man,” he said--in Leevi Madetoja’s classic Finnish opera “The Ostrobothians.”

“It was an amateur ensemble, and I was singing a brief role, but it’s a very important one,” he said. “That’s when the moment came.” It was the singing actor’s life for him.

He went on to audition for the Finnish Opera in 1966 and was immediately accepted to the chorus.

“From the chorus, they look for interesting faces and voices, and pretty soon I began to have chances, the first two years, every now and then, to get something bigger. I was picked out from the chorus. My voice did not necessarily stand out. My voice then was more lyrical and clear, more like a baritone, and in the chorus, you are not supposed to stand out.”

Still, building a career “was not easy,” he said.

His big break came when he filled in for an ailing colleague as King Philip in Verdi’s “Don Carlo” in 1969 and received excellent reviews. Since then he has sung major roles in Cologne, Zurich, Hamburg, Munich, Stuttgart, Covent Garden and at the Bayreuth Festival. His only prior appearance in Los Angeles was as Rocco in Beethoven’s “Fidelio” with Music Center Opera in 1990.

Salminen generally prefers staged opera to singing in concerts. “I’m very much a stage person,” he said. “I hate just standing. I’ve had no acting training, as such. I’ve learned by doing. I’ve had good directors, leading me in the right directions, and I’ve learned just by watching the style of the old masters. For me, acting is very much a question of the talent you’re born with and having an inner instinct of what to do.”

Originally, for his Philharmonic appearances, the basso was going to sing Mussorgsky’s “Songs and Dances of Death” in addition to the “Boris” excerpts. But the “Songs” were recently dropped.

“Actually, it was foolish of me to suggest doing something like that,” Salminen said. “The role of Boris is so huge, it requires so much, that adding the ‘Songs of Death’ would have been too much. It’s not the length of the role, but its deepness. It takes you totally when you sing it.

“But another reason [for the change] is that the third and fourth parts of the ‘Songs’ would have included some very high tessitura, for which I would have needed to use resources I’m not supposed to use to push the voice up.

“When we noticed this problem, I suggested maybe singing some Wagner or Verdi, but Esa-Pekka Salonen thought that he would like to stick to a Russian program.” So the orchestra will play the “Polovtsian Dances” from Borodin’s “Prince Igor.”

Salminen’s career takes him all over the world these days, and the time he spends in Finland can be measured only in weeks. Still, “home in my mind and home in my heart is in Finland,” he said.

“On paper, my home is in Switzerland. It has been in Switzerland for the last 15 years, and before that in Germany. But my wife and I have four homes--one in Zurich, one in Berlin, one in Helsinki and one close to Savonlinna in eastern Finland, where there is a famous summer opera festival. That is more like a villa, with a sauna.”

Salminen has been married to his wife, Arja, a former television producer, for 12 years. “As much as possible, we are together,” he said. “If I would be alone, I don’t think I could do it.

“Actually,” he joked, “the name of the company is Matti Salminen and Corp. But it doesn’t work alone. You need shareholders. There are three shareholders: Matti, Arja and our dog, Joonas, a 7-year-old miniature schnauzer.”

* Matti Salminen will sing excerpts from Mussorgsky’s “Boris Godunov” with conductor Esa-Pekka Salonen today, Thursday and Saturday at 8 p.m. and Sunday at 2:30 p.m. in the Dorothy Chandler Pavilion, Music Center, 135 N. Grand Ave. The program also includes Mussorgsky’s “Night on Bald Mountain” and works by Borodin and Scriabin. $6-$56. (213) 365-3500.