(CNN) -- Ten years after last voicing Autobot leader Optimus Prime on the original "Transformers" animated series, Peter Cullen decided to go to his first fan convention, BotCon, in Rochester, New York, after some coaxing from his daughter.
"I was taken aback by the response and the sheer love that was in the audience," he said.
"It became quite evident that (voicing this character) was a responsibility that I wanted to fulfill. I had no idea he was so popular."
That 1997 convention was the first of many for Cullen, who said that Optimus' influence over the lives of children made the character his favorite. "It's been wonderful to listen to the experience of growing up and how the character affected their lives in a good, positive way. It's a joy to know that I made a difference."
So, why all the adoration? "Optimus Prime is basically a bulletproof Abraham Lincoln," said iReporter and "Transformers" toy collector Shaun Martens.
"(He's) someone so competent, virtuous and level headed that you trust him more than yourself. To kids he represents the perfect father figure, someone who is strong in every way and holds the best interests of others above those of himself," Martens said.
"Optimus Prime is capable, loyal, forgiving, just, approachable, a brilliant strategist, merciful, selfless," said iReporter Kevin Farren.
"Optimus Prime can do no wrong. He can't even stay dead. If you ever needed a leader you'd want him to be Optimus Prime."
Ten years after that first convention, Cullen was asked to voice Optimus in the first of the wildly popular "Transformers" movie series, something for which he gives full credit to the fan base. This summer, he is playing the character in the third film, "Transformers: Dark of the Moon," as well as the new animated series on the Hub network, "Transformers: Prime."
"It was very important to me that he voice the character of Prime in the movie," said iReporter Cody Helms, who like Martens and Farren often check sites like Seibertron.com to interact with other fans and find out the latest "Transformers" news. "I believe he gives the character a better sense of humanity."
Like classic characters Bugs Bunny and Fred Flintstone, the voice of Optimus Prime is instantly recognizable for a certain generation. "You know it's him when you hear the voice," said Farren, who added that despite his disappointment in the movies overall, the highlight is hearing Cullen's performance.
Martens described Cullen's voice as "a perfect balance between warmth and authority."
Cullen said he is personally touched by how strong the response has been. "I remember an officer in the Marine Corps who had just returned from Iraq, and he gave me his golden anchor emblem from his officer's hat," he said. "He presented that to me and said this is how much you mean to me. There are no words to describe it, but I was humbled. That sticks with me forever."
Cullen -- who said that police officers have made similar gestures toward him -- came up with the voice because of his brother Larry, an officer in the Marine Corps. "I saw a difference in him when he came home. There was a maturity and calmness and understanding, and a very strong source of confidence, respect, caring and dignity," he said.
"I was called to audition and said goodbye to Larry, and I said I was auditioning for a hero. He said, 'Be tough enough to be gentle, you don't have to always be loud.' It stuck with me when I read the character description. I just echoed Larry's voice in the first few lines, and fell right into it. And I thought, boy, this feels like home."
When the producers of "Transformers: Prime" began casting, they knew that it was very important to get Cullen to play Optimus once again... and along with that, they felt strongly that they needed to get the original Megatron, Frank Welker, as well.
"Those two guys love each other," said executive producer Jeff Kline. "They're so obviously happy together that you get better stuff from the cast. That stamp of approval on what we were doing went a long way with the fan community, as well."
Cullen said that he and Welker go back to the 1979 Saturday morning cartoon, "Mighty Man and Yukk," about a miniature superhero and a dog so ugly he had to cover his face with a dog house.
"He played the dog, and I played Mighty Man," he said. "Now, sometimes we won't see each other for a while, but we'll inevitably end up in the same studio together and reinforce our great appreciation for each other."
That camaraderie extends to younger members of the "Prime" cast, as well. "The most surprising thing is being in the room with Peter and Frank and all of these guys whose careers I've followed for so long and the fact that they were still so excited to be there, and so grateful after all these years -- especially Peter, he's done it all, and he's like a little kid in there and just as excited as we are," said Steven Blum, who plays the villainous Starscream.
"He's not the huge man you would expect him to be listening to his voice. He's a normal size guy, but he opens his mouth and it's almost as though the jaw would unhinge and the windows start to flex with all the vibrations coming out. It's just astonishing."
On the flip side from Optimus' heroism, anime veteran Blum explores the darkness of Starscream while getting into character. "I just go as dark and delusional as I possibly can and sort of build my way up from there," he said. "Sprinkle in a little deviant and cowardly and megalomaniacal and I think from moment to moment, he's one or all of those things."
"He's a villain that is so completely out for himself that it actually works against him," said Martens, who counts Starscream as his favorite "Transformers" character. "You never know if he's going to follow Megatron's plan against the Autobots, or try to off Megatron and take control of the Decepticons himself."
Between good and evil, Blum is somewhat on the fence as to which he prefers. "The villains are certainly therapeutic. I get to act out all the badness that I am not really allowed to do in my day to day life," he said. "But I like the heroes too, I do like setting a good example for kids once in a while instead of turning them into demented monsters. They both have their charm, but I would say more days than not, the villain is more fun to play."
Not surprisingly, Cullen feels differently: "I played a villain - Venger in 'Dungeons and Dragons' - and I got some feedback that it was pretty scary. I'm not the kind of guy that likes to scare people. If it's going to have an entertaining value, it's got to be funny or inspiring. The evil part of it is part of the acting generator but it's not one of my favorites."
One burning question for both actors: do they own action figures of themselves? "I used to have Transformers figures, and I think I broke them because I played with them too much," said Blum.
"I have the original G1 figure (from the 1980s)," said Cullen. "I even broke a portion trying to configure it -- it ended up on a shelf where it remains in pieces, several pieces I might add. Nonetheless, it's quite important to me, it was my first one and I cherish it."
Nowadays, Cullen keeps the figures in a closet, to bring out during birthdays and holidays for his grandson. "I love the 18 wheeler that transforms and speaks at the same time. I was knocked out by that one. He will get that at Christmas."
True enough, "Transformers" transcends generations, as Cullen has seen for himself.
"My grandson is turning five in August and we were at dinner at a pizza house several days ago. He got up on his chair standing next to his dad and said 'I'm Optimus Prime!,' and I just dropped! He's into 'Transformers: Prime' and it just made my heart swell. That was a total surprise -- it knocked me out."