"I played little clubs, doing my apprenticeship," he said. "It was hard work, performing for hours nonstop. But it gave me a good grounding and the experience I would need in later years when performing before large crowds."
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He said he managed a few appearances on British television and toured with other British singers.
"But my career was going nowhere," Humperdinck noted. "So I decided I needed to change my image."
The singer had gone prematurely gray in his 20s, "so I dyed my hair jet black and grew long sideburns. In fact, I started a trend. I had sideburns long before Elvis and often joke that he stole my look."
The most important part of his image overhaul, though, was to change his name to the unforgettable Englebert Humperdinck after the 19th-century Austrian composer.
"I'm not sure I would have accomplished all that I have if I hadn't done that," he admitted.
It wasn't long after he had signed a contract with Decca that he had a chart-topping hit with "Release Me."
"It went to No. 1 in the UK and prevented The Beatles from taking that spot with their double-sided record 'Penny Lane/Strawberry Fields'", he said. "The melody, the lyrics really caught on. And to this day, it's one of my most requested songs."
While he was part of the British Invasion, Humperdinck said his singing style was closer to Tom Jones than The Beatles.
"But we all came from the era of hard knocks — one where you worked your way up the ladder of success, performing long hours in small clubs, working for not a lot of money and paying your dues. That's what made our success so appreciated."
Throughout the years, Humperdinck said he has developed worldwide following. And his fans have remained loyal.
"The nice thing is that the people who were my fans back in the 1960s and 1970s are now bringing their children and grandchildren to my concerts," he said. "There is such a wide range of ages that are part of my audiences. There was an 8-year-old boy at a recent concert who knew the words to every one of my songs."
When he first started out in the business, Humperdinck said he "never realized how far my career would go. I never could have imagined the level that I would reach."
His secret to success?
"The day I try to analyze success is the day it disappears," he said. "First, though, I think I've been very lucky. And I've never stopped learning, never stopped trying to improve. The more I do it, the more experience I get. And I think that's something that never ends, regardless of your age."
Humperdinck said still loves performing before an audience and feels his voice hasn't lost its strength.
"Maybe I've dropped a note in range, but the power is still there," he shared. "Otherwise, I wouldn't be out there doing this. People tell me I sound the same as they remember 40 years ago."
Humperdinck said he enjoys listening to current singers, noting "there's a lot of talented people in the music world. I listen to everybody. I also watch the music shows, like 'X Factor,' 'The Voice,' and 'American Idol' to see what young performers are doing. You can always learn something from others."
But, mostly, he added, "I enjoy listening to the greats of music — Paul McCartney, Elvis, Elton John and Michael Jackson."