Michael Buble no longer has to rely on his grandfather offering free plumbing to get on stage.

The singer chuckles at the memory as he relaxes in his San Francisco hotel, about to head for – where else for this entertainer who already has circled the world many, many times to take his music to the people? – the airport.

It was his granddad that had asked Buble as a boy if he would learn some of his favorite pop standards as a favor to him.

Buble was a solid student, winning a local talent contest, but then being disqualified for not being old enough.

That’s when granddad swung into action, bartering his plumbing skills if local musicians would let Michael on stage to perform a few numbers with them.

Since then, the Vancouver native has played five sold out nights at Sydney Opera House and performed for Prince Charles at the Royal Variety show in the Royal Albert Hall. And not one wrench or plunger had to be wielded, nor a single pipe thawed by granddad for the privilege.

In fact, now its Buble, whose worldwide CD sales total millions, who has been able to do good deeds for his grandfather.

“I was able to bring him to Italy with me for concerts where his family is from and his roots are based, Buble said enthusiastically.

That was his grandfather’s way of measuring his grandson’s success.

“He would ask me, after my first record came out, ‘Are you famous in Italy yet? Is anything happening in Italy yet?’ ”

Buble had to settle for giving him rosy reports of how well he was doing in America, Europe, South Africa and elsewhere. “When we hit in Italy we hit big and he couldn’t get over it,” he said.

Buble invited him to Italy and his granddad received the green light from his heart doctor to fly.

"We got off the plane and he turned into a 14-year-old," he said. Buble played to 5,000 to 10,000 people nightly in gorgeous amphitheaters with young kids screaming. He invited his grandfather on stage every night to take the microphone and say hello in Italian. Each night granddad became braver. By the end of the tour he was grabbing the microphone and greeting the audience enthusiastically. "He was having the time of his life,” Buble recalled.

As is Buble.

"I think I’m lucky. I hope that people can tell I’m sincere. I think maybe they can tell that there is something authentic about what I’m doing," he explained. "I’m not saying I’m brilliant or reinventing or doing anything new. I just think people can tell I’m sincere about what I do."

He said he has worked on having a solid voice and really trying to be a great interpreter of great songs. Buble sings a song each night for his grandfather from the stage: "Have I Told You Lately That I Love You."

In this city of the Golden Gate, in which one leaves his or her heart, it seems most appropriate that Buble makes the transition now to speaking of one of his other heroes, Tony Bennett, as well as others.

"I look to Sinatra and Bennett and Bobby Darin and tried to borrow from them," he explained. "I’m lucky enough to say I got to hang out with Tony Bennett a lot and even people like Englebert Humperdinck, who has been really cool, and to ask them questions and get their support. That’s been huge."

It’s suggested that Buble, still a young man, could very easily have fit into the heyday of their era, and even the period when the ink was still wet on the Great American Songbook.

He smiled, then offered: "I wish I was more nostalgic about it, but I’m really not." Part of it is being sincere, being himself and being OK with it, he said.

"I was born in ’75. I don’t know what to do without a remote (he laughs). I’m a young guy singing songs that are timeless, taking my experiences and wins and losses and the love my family gave me into my music. These songs are timeless."

Different people take different things from his efforts. Some forge an emotional attachment with the music. They listen to a song like his self-penned "Home" on his album "It’s Time," and think about someone they missed, or they might listen to another cut, like "Try A Little Tenderness," and be washed over with longing.

"Everyone has a different take," he said. "I try to be simple. I believe 85 percent of the public, they just like music."

Most people don’t really care what category music fits in, he insisted. He said he is not a pop or jazz singer, but an entertainer who interprets beautiful songs.

While sometimes critics plead with him to pick a style, he said there is no category for what he does. "It’s taking my love of standards and adding it to (his producer) David Foster’s pop sensibility. It’s almost making a hybrid that doesn’t end up in jazz or sitting in pop. That’s why I wrote ‘Home’ so I could cross over to that audience that hadn’t been exposed to what I’m doing."

When you’re working with standards, you don’t have to worry about if there will be any filler on your album, said Buble, who latest studio album is “Call Me Irresponisble.”

"I have to go to the record store and buy too many albums and I only wanted a song or two. What I love so much about standards is you’ve got 13 out of 13 songs you want," he explained.

Buble said he is simply a fan of music. "I listen to all these songs (of a variety of styles). I’m just taking songs I love and thinking, ‘How can I make this mine?’ Is there a way to reinvent this tune?’ It went number one once, why can’t it go twice?’ "

He insists that these songs should not be discarded. "Some of these songs should be celebrated. I’m an interpreter," he said.

In selecting material, he first must relate to the lyrics in the same way an actor looks at a script. And he has to be able to say, "I can believe these words." "And if I can, everybody can believe," he added.

For “Call Me Irresponsible,” he chose the words of Leonard Cohen, Eric Clapton, Cy Coleman, Gamble and Huff, Eric Clapton, Mel Torme and others, as well as two self-penned originals, including the first single, the uplifting love song called “Everything.”

His longtime producer David Foster (who has worked with Whitney Houston, Barbara Streisand, Josh Groban and Celine Dion, among others) makes a good artist great, he said.

"It’s like working with Beethoven. The man simply is the greatest. People give him flack and reviewers are tough on him, but there is just no denying this man is incredible. He hears things before they happen, like a good athlete." Foster, a 14-time Grammy winner recipient, certainly knows talent.

Buble, this "10 year overnight sensation," which Foster first saw entertain at a wedding reception, has the ability to be one of life’s legends wrote one magazine.

The entertainer said he is not sure how to react to such an amazing compliment. "I’m still at that stage where I don’t want it to go away. Fear of failure drives me. It’s a beautiful thing that writer said and it makes me feel good when I hear something like that, but I really can’t let it get to me. I can’t believe it’s true. If I do I have to believe the reviewers who say I’m a piece of crap and scum and I have no business singing."

There may be better singers, he acknowledges, but none with as much passion for the music he does.

"It’s weird how melody and harmony added correctly to the right lyrics can touch off an emotional response you really have no power over," he said. "It either gives you a burst of energy or you feel the moment or it takes you back."

He sees all ages embracing that, seeking that feeling. They’re finding it in people like Norah Jones, Josh Groban and, he hopes, in Michael Buble.

Music has, and continues to be, the fabric of his life. "I don’t know if I could live without it. It has inspired me since I can remember, since I was a little kid," he said. "It drove me to do things that I didn’t think I could do. And I promise you I’m just a regular dude from a small city in Canada."

Buble tries to keep it all, including his worldwide success, in perspective. "I look at my dad and grandpa and I hope I can be half as successful as they have been," he said. "They are regular blue collar guys whose families love them to death. They are loved unconditionally by me and their relatives. One day this may all go away. If it does I have what’s important."