LOS ANGELES (Reuters) - They might be small and furry but their high-pitched voices are reaching a huge worldwide audience.
More than 50 years after the mischievous Chipmunks were born as a novelty song, the animated trio have squeaked up a $1 billion empire of more than 45 million records, TV shows, and live action movies -- all with the very loud catch-phrase "Aaallvviinn!"
Their latest movie outing, "Alvin and the Chipmunks: The Squeakquel", arrives on DVD on Tuesday (March 30) packed with sing-alongs, behind the scenes features and interviews.
The enduring appeal is mostly because they are not simply talking animals, but creatures with a heart, said their human parents, Ross Bagdasarian Jr. and his wife Janice Karman.
"The characters deal with emotions like pain, happiness, jealousy and family relationships in every show or movie that we do. The fact we are touching on subjects that people can always relate to and are timeless, is something that keeps the characters alive," Karman told Reuters.
The Chipmunks -- Alvin, Simon and Theodore -- were created in 1958 by Bagdasarian's father, Ross Bagdasarian Sr., and had their first hit with a novelty record called "The Chipmunk Song". The trio went on to star in a TV cartoon series and later a Christmas special, dozens of music albums, a live stage show and their first feature film in 1987.
What also distinguishes the Chipmunks and their female singing rivals, The Chipettes, from a crowded market of anthropomorphic hamsters, cats and pandas, is their voices.
But as Chipettes voice actresses Amy Poehler, Christina Applegate and Anna Faris soon found out found for the 2009 movie, getting the right amount of squeak is harder (and slower) than one might think.
Chipmunk voice actors are required to speak much slower than normal, and the squeak is achieved by speeding up the tapes afterward.
"The girls had no idea. They had been practicing their chipmunk voices," said Karman, who invented and has voiced all three Chipettes for more than 20 years.
"By slowing the voice down and then speeding it up, you still get the warmth of the character. It's a tough way, but it is the best way."
It also takes about 20 times longer than normal movie voice-overs. "You have to do a variety of takes but you don't know until you turn it back to speed whether it has worked, or is understandable, or has the emotion, or whether the comic timing is right," she said.
Despite weak reviews, the "Squeakquel" movie took in about $440 million at the worldwide box office following its release in December -- about half of which came from fans in nations like Australia, Brazil, Mexico and from Europe.
It followed 2007's "Alvin and the Chipmunks," which hauled in $360 million around the world, surprising even some jaded Hollywood box office watchers with its success.
Movie studio Twentieth Century Fox earlier this month announced plans for third film, this one in 3D, set for 2011.
It's all a far cry from the humble beginnings of Alvin, Simon and Theodore as lip-syncing puppets managed by their human father David Seville -- the alter-ego of Ross Bagdasarian Sr. who died in 1972.
"My dad was a really, funny smart talented guy but he had a very short attention span," said his son Ross. "He had done TV shows and merchandising and music, but after about seven or eight years, he had done everything he wanted to and he retired them in about 1966. So I think he would be amazed that they are still going strong 52 years later."
Editing by Bob Tourtellotte