T-Pain would not have picked the monster costume if he’d known he was going to stick around.

“I figured I’d get voted off super-quick,” the hip-hop star said of his stint on “The Masked Singer,” Fox’s wacky competition show that put T-Pain and other celebrities in elaborate disguises as they waged vocal war with one another this past winter. “So I was like, ‘Lemme just wear the most ridiculous thing I can before I get up out of here.’?”

As viewers of the surprise-hit series know, that’s not what happened.

After vanquishing rivals including Gladys Knight (who dressed as a bee) and Donny Osmond (a peacock), T-Pain won “The Masked Singer” in February, finally removing his oversize monster head to reveal his identity to a shocked judges’ panel.

It was perhaps an unlikely victory for a singer associated more than any other with Auto-Tune, the vocal-processing software T-Pain’s been using since the mid-2000s — in songs like “Buy U a Drank” and “Can’t Believe It” — to give his voice its signature emotional-android effect.

“The soul that you put down on this show, man, I am just amazed,” Robin Thicke, one of the “Masked Singer” judges, told him on the finale.

But T-Pain knew he could sing without Auto-Tune, which for him (and many of the artists he’s inspired) isn’t a corrective tool so much as an aesthetic device.

The reason he expected to lose was because he’d been “trained,” as he put it on a recent afternoon, to believe that any creative idea he had would result in failure.

“What do they call it when you make somebody think they’re crazy?” he asked. “My wife knows the word.”

Gaslighting?

“That’s it,” he replied. “I got gaslit. Big time.”

Sipping tequila as he sat in a Beverly Hills hotel room, T-Pain seemed to be in high spirits the day before he began a tour behind his new album, “1Up.”

The 33-year-old singer, who lives with his wife and children in Atlanta, had come to town to host last month’s televised iHeartRadio Music Awards — another gig, like “The Masked Singer” and his tune from “The Lego Movie 2” soundtrack, that’s widened his audience 15 years after he got started.

“I went on an Instagram rant the other day and somebody told me, ‘Little white kids are looking at you now — stop your cursing!’ ” he recalled with a laugh. “I was like … you’re right.’?”

Yet not so long ago, things were worse for T-Pain. After years of creating hits for himself and with other artists such as Kanye West and Flo Rida, the singer says his record label, RCA, lost interest in him and his work in the wake of a backlash against Auto-Tune crystallized by Jay-Z’s 2009 single “D.O.A. (Death of Auto-Tune).”

He described a listening party he threw at his home — “catered the whole thing, hired bartenders, flew everybody in” — shortly before his excellent 2011 album “Revolver” was due to come out.

“I start playing the music and by Track 2, everybody’s in full conversation, including the president of the label, who was at my house to hear the record that he’s gonna be held accountable for.

“And he’s talking super-loud about something he did two weeks ago.” (An RCA representative didn’t respond to a request for comment.)

T-Pain said he eventually blew up at his guests, telling them, “If this was Chris Brown’s party, y’all wouldn’t be doing this.”

“And literally the day after that,” he said, the label withdrew its support. “No promo, no interviews, no nothing.”

The lack of enthusiasm stung, T-Pain admitted; it also led to a creeping worry that maybe he was wrong to think his music was still any good.

What was really vexing, though, was that RCA wouldn’t drop him even when he begged to be let go. The label, he said, didn’t want another company to sign him lest Auto-Tune come back into vogue and he find success elsewhere.

So with one album remaining on his contract, he said he asked, “What kind of music y’all want me to make?” The result was 2017’s tellingly titled “Oblivion,” on which he bent his trademark sound toward the popular trap style.

His take on the record now? “Hate it,” T-Pain said. “It just wasn’t my music, man. That was T-Pain being fake.”

Which brings us back to today. With new management and a new label, Cinematic Music Group, the singer says he’s relearning to trust his instincts — and just as Auto-Tune has resurged among youthful hip-hop hitmakers like Juice WRLD and Lil Uzi Vert, whose music proudly accentuates the technological effects Jay-Z bemoaned a decade ago.

T-Pain sees himself at the beginning of a sonic lineage that extends through Lil Wayne, West, Future, Chief Keef — “and then literally everybody else,” he said with a laugh.

“If you put that combination in a pot, you could make every other hip-hop artist right now.”