LONDON • "I'm not going to cry," singer Adele said. She was practising with her band at Music Bank rehearsal studios, a warehouse space in South London, and had just finished When We Were Young, one of the torchiest ballads on her new album, 25.

It is a song about running into an old flame who confesses, "I still care" and then, tentatively, asks, "Do you still care?".

Adele can get caught up in her own songs and she would not want to change that.

"For me to feel confident with one of my songs, it has to move me," she said. "That's how I know that I've written a good song for myself - it's when I start crying. It's when I just break out in (expletive) tears in the vocal booth or in the studio and I'll need a moment to myself."

That heart-on-sleeve emotion, conveyed by a gorgeous voice, has made Adele, 27, one of the most universally beloved singers and songwriters of the 21st century.

Adele, whose last name is Adkins, won the Grammy for Best New Artist with her 2008 debut album, 19. She multiplied her audience with 21, her 2011 album full of breakup songs - angry, regretful, lonely, righteous - that used modern production touches around vocals filled with old- fashioned soul. It has sold 30 million albums worldwide, 11 million in the United States.

Last Friday, 21 was deemed by Billboard magazine to be the greatest album of all time based on chart position; the soundtrack of the 1965 Julie Andrews movie The Sound Of Music came in second. Adele racked up the most weeks - 24 - for an album by a woman atop the Billboard 200 album charts and saw 78 weeks in the top 10, Billboard said in a ranking based on chart positions dating to 1963.

Beyond the power of her voice and the craftsmanship of the music, 21 communicated a palpable sincerity and urgency, the feeling that its wounds were still fresh.

"She's got this incredible intuition about what's right and what's real and what suits her," said Paul Epworth, who wrote and produced songs with Adele on 21 and the new album. "She's the sharpest, most instinctive artist I've worked with. She's pure gut, pure intuition."

The question that loomed over her in her four years between albums was how - or if - she could follow her blockbuster with something equally striking.

"There is no beating or redoing 21," said Ryan Tedder, another producer and songwriting collaborator for both 21 and 25. "You're lucky if at one point in your life you stumble across a unicorn in the woods. The odds that you find a second unicorn are remote and she's aware of that. I think that 25 will be enormous, regardless of anything. But that wasn't the goal. She wanted to put out the best thing that was the most honest."

At this rehearsal, Adele was a musician above all. She moved decisively through new songs and old ones in preparation for TV appearances and a Radio City Music Hall concert (and NBC TV taping) tomorrow, three days before the worldwide release of 25 (XL/Columbia) on Friday.

And she sang in full-throated glory, capturing the vengeful bite of past hits such as Rolling In The Deep and the hushed suspense and pealing chorus of her new one, Hello.

Adele had largely maintained public silence while recording 25. Her reticent re-emergence was a brief, anonymous TV advertisement, first shown on Oct 18 during The X Factor in Britain. It was the beginning of Hello: just sombre piano chords, her voice and the lyrics - "Hello, it's me/I was wondering if after all these years you'd like to meet" - with no other information.

Unlike most other pop hitmakers her age, she barely uses social media. It is one of the many charmingly old-fashioned aspects of her career. But she does have a Twitter account and she could not resist looking online to see if her voice had been recognised. When she did, she saw only three tweets.

She panicked. "I was like, 'Oh, no, I've missed my window,'" she said over a cup of tea a few days after the ad. "'Oh, no, it's too late. The comeback's gone. No one cares.'"

But then, she recalled, her boyfriend Simon Konecki joined her at the computer and showed her that thousands of other tweets were pouring in. Once Hello was released on Oct 23, more than 1.1 million people bought the song as a download in its first week in the US alone and tens of millions streamed the audio and watched the video clip.

Hello does not just introduce 25; in many ways, it sums up the album. On it, the rage and heartache of 21 are replaced by longing: for connection, for youth, for reconciliation and for lifelong bonds. Like other songs on the album, Hello is filled with thoughts of distance and the irrevocable passage of time, of apologies and coming to terms with the past. Musically, the song has verses with just voice and piano followed by ringing choruses; similarly, the album as a whole switches between organic, unplugged ballads and booming modern pop.

As she wrote the album, Adele was no longer the heartbroken avenger she had been on 21; she had become an internationally recognised star and, at 23, a mother.

In October 2012, she had a son Angelo with Konecki. She collaborated on writing Skyfall, the James Bond movie theme that would bring her an Oscar, while she was pregnant.

She took time to raise her infant as she pondered what to do next.

She made her first efforts to write new songs in 2013. Initially, she said: "I didn't think I had it in me to write another record. I didn't know if I should. Because of how successful 21 was, I thought, 'Maybe everyone's happy with that being the last thing from me. Maybe I should bow out on a high.'"

Of course, she changed her mind.

"As time went on, I realised I had no choice," she continued. "I have to write more music for myself and there's nothing else I want to do."

NEW YORK TIMES, REUTERS