To a generation of TV watchers, Romero established the character as a kid-friendly bad guy, cast against type as a campy, high-pitched, R-rolling Joker in the ’60s “Batman” TV series. For the 1989 “Batman” film, Jack Nicholson lowered the nemesis’ register, making him more menacing but still cartoonish.

Both voices informed Hamill’s portrayal in the bleaker “Batman: The Animated Series” in the early ’90s. Hamill initially voiced other roles on the series; soon the producers asked him to take a crack at replacing Tim Curry, who wasn’t quite right for this Joker.

When Hamill received the audition script, his copy read: “Don’t think Nicholson.” So he reached back to his Broadway experience as Mozart in “Amadeus” — the composer was said to have stunned the imperial court in Vienna with his donkey’s bray of a laugh. Hamill tossed in notes from the Blue Meanies in the Beatles’ film “Yellow Submarine” and the 1930s “Dracula” actor Dwight Frye, among other things, and won the role.

“I looked at this drawing, and he seemed to be all teeth, all teeth, all TEETH,” Hamill said by phone from his Los Angeles home, drawing out the Blue Meanie creepiness of the line. “I don’t want there to be a ‘Joker laugh’ — I want there to be a palette of colors, sinister, intimidating, gleeful, insane, every emotion that you can think of. It’s a large part of how he communicates.”

Besides that series, which ran from 1992 to 1995, Hamill has played the Joker in multiple spinoffs on television and in video games. With his arsenal of laughs — on the phone, he delightfully offered a low, chuckling “hmm-hmm-hmm-hmm,” a softly whooping “hoo hoo” and what he called a “big, broad ah-hah-HA-HA-HA-HAH!” — Hamill set the standard for the character’s vocal depth and richness.