But perhaps more remarkable, Ms. Clarkson, 35, has remained a major pop player for a decade and a half without checking the usual pop-star boxes. She’s not an enigmatic, larger-than-life figure like Beyoncé, or a social-media chess master like Taylor Swift; she’s not an outsize persona like Lady Gaga or a style icon like Gwen Stefani. She’s not known for dancing, splashy tabloid drama or sparring with other stars — though she’ll shut down body shamers and anyone who spews negativity at her on Twitter. Like Adele, she is known for her tremendous voice, the vulnerability and relatability of her songs and her fearlessness when it comes to speaking her mind.

“I don’t want to be trained to talk,” Ms. Clarkson said in an unsurprisingly blunt interview the day after her radio soiree. “I’m not a puppet, I have a brain.” Soon she will bring her frankness back to television, as a coach on “The Voice” in 2018.

Ms. Clarkson is hoping “Meaning of Life,” out Oct. 27, speaks loudly, too. After finishing her RCA contract, which came with her “Idol” victory and was an unhappy partnership she refers to as her “arranged marriage,” she is making what she considers her first real artistic statement. Leaving behind the pop-rock that became her signature sound in favor of the soul that has captivated her since her youth in Texas, she is asking her audience to leap with her into more mature, nuanced sonic and emotional territory. The album’s first single, “Love So Soft,” sets the tone — it’s a swaggering track packed with girl-gang backup vocals and horn blasts that climaxes with a blistering high note. It sends a clear message: The Diva Is Present. For the first time in 15 years, Ms. Clarkson feels as if she is driving her own career. If she fails — and she recognizes the risks — at least she crashes on her own terms.

While contemporary soul singers have penetrated the pop market in recent years, “It definitely is still a harder sell than ‘Since U Been Gone 2.0.’ It’s not the easiest route,” she said. “But it’s the only option.”