The cause was a heart attack, his manager, Katherine Olsen, said.

Giordani appeared more than 240 times with the Met in 27 roles, including in two company premieres, five new productions and the opening nights of two seasons.

When he opened the 2006-07 season, the first of Peter Gelb’s tenure as general manager, in Puccini’s “Madama Butterfly,” Anthony Tommasini wrote in The New York Times that Giordani sang “with full-bodied Italianate passion; warm, rich tone; and clarion top notes.”

“Clarion” and “passion” were adjectives often used to describe Giordani at the height of his powers, in the early 2000s. He “sang like a god” in a 2002 concert performance of Cilea’s “Adriana Lecouvreur” at Carnegie Hall with Opera Orchestra of New York, Anne Midgette wrote in The Times. It was, she added, “a rock-solid performance at an ideal pitch of fortissimo passion.”

Marcello Guagliardo was born on Jan. 25, 1963, in Augusta, a small town on the eastern coast of Sicily. He was the youngest of four sons of Santina, who was a housewife, and Michele, who had been a prison guard but by then owned a gas station. (Soon after starting his international career, Giordani adjusted his name to be simpler to pronounce and spell.)

When he finished school, Giordani worked in a bank, but quickly grew bored. His father encouraged his interest in music.

“He loved opera,” Giordani told The Times in 2007. “He heard me singing all the time when I was a kid. Maybe he always dreamed that one of his sons would be an artist.”

Tall, handsome and fervent — “Now there’s a tenor,” star singer Neil Shicoff once marveled to Olsen — Giordani had a success in Spoleto, Italy, with Verdi’s “Rigoletto,” in 1986.

His debut at the Teatro alla Scala in Milan came two years later, in Puccini’s “La Bohème,” as he began to sing throughout Europe. He made his American debut in 1988, singing Nadir in “Les Pêcheurs de Perles” with the Portland Opera in Oregon.

He met Wilma Ahrens that year, when she was working for the presenter at an engagement in Lucerne, Switzerland; they married two years later. She survives him, as do their two sons, Michele and Gerard Andre, and his three brothers.

“I learned my profession onstage,” Giordani told The Times. “I didn’t have a musical background. I had no conservatory training. I don’t play an instrument.”

That lack of firm technical grounding soon began to haunt him, and by the early 1990s, he was having vocal problems. “The tenor voice should be like sunshine,” Giordani told The Los Angeles Times in 1998. “My voice was sounding old already, too dark.”

Giordani began a new training regimen, under the guidance of the prominent teacher William Schuman, that saved his natural talent.

“The first thing he did was open my body and let me trust my voice again,” Giordani recalled a decade later. “In the past, my voice was my enemy. But for 10 years, it’s been my best friend.”

Giordani remained committed to fostering healthy voices and careers; in the early 2010s, he established the Marcello Giordani Foundation to nurture young singers.

He made his first appearance with the Met in the summer of 1993, in Donizetti’s “L’Elisir d’Amore,” as part of the company’s series of concert operas in city parks. The big tenor aria, “Una furtiva lagrima,” was, Alex Ross wrote in The Times, “a stirring display of direct emotion.”

His debut at the Met’s Lincoln Center home came two years later, in “La Bohème.” He quickly established himself in the ardent lover leads in touchstones of the repertory, mostly Italian works by Verdi and Puccini, but also as Lensky in Tchaikovsky’s “Eugene Onegin,” the title character in Berlioz’s “La Damnation de Faust,” Énée in that composer’s “Les Troyens,” Des Grieux in Massenet’s “Manon,” Don José in “Carmen” and, aptly, the Italian Singer who makes a fervent cameo in Strauss’s “Der Rosenkavalier.”

In Opera News magazine, David J. Baker praised Giordani’s “controlled, sensitive and robust singing” in the Met premiere of Berlioz’s “Benvenuto Cellini” in 2003. But while Marion Lignana Rosenberg, writing in the same magazine a year earlier, described his “ringing, brilliant” high notes in the company premiere of Bellini’s “Il Pirata,” she added that “there is a hardness to his tone that is ill-suited to Bellini’s long, supple cantilena.”

In 2008, he was the tenor soloist in a Met performance of Verdi’s Requiem dedicated to the memory of Luciano Pavarotti, and, in December 2010, he starred in Puccini’s “La Fanciulla del West” on the 100th anniversary of the work’s world premiere at the Met, in a role sung in 1910 by Enrico Caruso.

He sang in Verdi’s “Simon Boccanegra” at the Royal Opera House in London in 1997 under Georg Solti, in what turned out to be Solti’s final operatic performances before his death later that year. In 2003, Giordani appeared in the Paris Opera’s first production since 1863 of the original French version of Verdi’s “Les Vêpres Siciliennes.”

But for all his successes in opera houses, his most glorious nights may well have been his Carnegie Hall performances with Opera Orchestra of New York and its founder and conductor, Eve Queler. With that company, he sang works including “Adriana Lecouvreur,” Ponchielli’s “La Gioconda,” Meyerbeer’s “Les Huguenots” and “L’Africaine,” and Rossini’s “William Tell,” in 2005 — with which Giordani stopped the show near midnight with the cabaletta “Amis, amis, secondez ma vengeance.” When the cheers wouldn’t stop, he sang the aria again.

“I’ve never seen a crowd react that way,” Schuman, his teacher, said. “A true riot broke out. It was like someone scored the winning touchdown at the Super Bowl. He was capable of incredible things.”

This article originally appeared in

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