A few years back, a critical mass of musicians started making R&B steeped in the sort of art-damaged signifiers indie rock has traditionally claimed as its own. This wasn’t the first time rhythm & blues had pushed boundaries; legendary figures from Curtis Mayfield to Prince to Missy Elliott managed to get some of the most mind-bending sounds of their respective generations on the radio. Still, the sheer number of musicians making R&B their vehicle for sonic exploration demanded attention: How To Dress Well’s bleary dreamscapes and the Weeknd’s nightmarish seductions; Solange Knowles and Blood Orange’s stylish retro dance-pop; darkly crystalline R&B-inflected electronica from Holy Other and Purity Ring; Technicolor psych-pop concept albums from Frank Ocean, Miguel, and Janelle Monaé. As Nitsuh Abebe noted in a roundup of this emerging trend — God bless you if you’ll join me in letting the acronym die — some of these musicians were arriving through traditional R&B channels (usually the black performers) and others through traditional indie-rock outlets (usually the white ones). They were unknowing co-conspirators, not a unified movement. That’s partly why this wave of R&B innovations felt so big: Black musicians were experimenting with traditionally white sounds at the same time white musicians were experimenting with traditionally black sounds, all of them blurring into a new R&B avant garde that was far too colorful to be described as gray. The accidental scene was, to borrow a word from Miguel, kaleidoscopic.

By 2012, R&B was a flourishing subgenre within underground music. Its reach has only continued to expand since then; two years on from a year that made R&B fans out of indie-rock dopes like me, R&B is feeling more and more like alt-culture’s new normal. It is no coincidence that Ariel Rechtshaid, a producer who scored his biggest hit with Usher, was behind several of the most acclaimed and successful “indie” albums of 2013. The underground (and the segment of the mainstream the underground claims as its own) is far too diverse to be reduced to just a continuum between Rhye’s pillow talk and Autre Ne Veut’s computerized soul abrasion, but that continuum does exist, and it has become a favored sweet spot among the bedroom virtuosos and urban cool kids that tend to drive musical trends — not to mention some of mainstream R&B’s foremost superstars. The likes of Drake and Beyoncé are prisms, soaking up their favorite experimental sounds and refracting them back into the underground. Art-school musicians are just as likely to cite those two as primary influences these days as Ian Curtis or Lou Reed.

As such, new musical acts performing R&B with indie sensibilities are springing up all around the globe. From Austria via England there is SOHN, a sighing, skittering hi-tech balladeer. From England via California there is Banks, a stylized, sad-eyed seductress emanating ominous vibes in the Weeknd’s wake. From California via Holland there is Young & Sick, a visual artist turned digital Daryl Hall with a flowing blonde mane to match. The list goes on: Portland producer Shy Girls copies How To Dress Well and covers Brandy. Stockholm’s Naomi Pilgrim, a former backup vocalist for indie-pop singer Lykke Li, churns out gurgling, morphing, crystalline soul tracks. London fashion freak FKA twigs splits the difference between Bjork and Aaliyah. Ontario’s Jessy Lanza trades in sleek electronic slow jams akin to Junior Boys, a group that helped clear the way for this movement a decade ago with its breathy synthetic comedown music. These R&B upstarts run the gamut from dramatic (Movement, Doe Paoro) to breezy (SAFIA, Jacques Greene) to off-kilter (Kelela, Matthewdavid), and they are legion.

As this spring’s album release schedule has evidenced abundantly, even those whose sound started out nowhere near R&B are jumping on the soul train. White Hinterland’s Casey Dienel, whose Wikipedia photo pictures her strumming a ukulele, has taken the next logical step from the synth sounds of 2010’s Kairos to the vocal trills and big bass of Baby. Six years ago she was playing coffeehouse jazz and operatic folk-rock, but the current has carried her to songs like “Ring The Bell,” which could pass for an unpolished Rihanna in a pinch. TEEN, the sister-driven Brooklyn combo that two years ago specialized in rumbling fuzzed-out psychedelia, has taken a page from that other sister band and openly embraced their breathy ’90s idols on the new The Way And Colour. The resulting psych-R&B of songs like “Not For Long” is fascinating and inventive, in part because it forces TEEN’s fuzz-crunch and head-trip elements to fight for space with the airy soulful bounce. The Way And Colour is in line with the flavor of the moment, but it has its own flavor too.

Boots, the producer behind much of last year’s vaunted Beyoncé album, has released a steady stream of dusky R&B singles this year, including one actually featuring Beyoncé, but not that long ago he was making Cults-like kitchen-sink indie pop under the name Blonds. Wye Oak’s transition away from moody guitar spasms toward moody bass-synth grooves — lead singer Jenn Wasner’s response to a falling out with her guitar — has been well-documented, but it’s more of a change in clothing than a change of heart. Wasner’s dalliances with R&B under the guises of Flock Of Dimes and Dungeonesse were far more radical genre adventures. Still, the distance between Shriek’s bass wallops and those that still reverberate through indie rock’s more abrasive corners feels formidable. Even the fiercely individual Merrill Garbus can be found dabbling in R&B on her new tUnE-yArDs album Nikki Nack. The deep cut “Wait For A Minute” trades tUnE-yArDs’ usual yawps and polyrhythms for something mellower and smoother, a sort of boom-bap sequel to Gwen Stefani’s “Hollaback Girl.”

Earlier on Nikki Nack, Garbus sings, “When I see you changing, it makes me think that I could change too,” which just about sums up the climate. R&B is the “floppy on top, shaved on the side” of genres right now, the default way for indie-rock artists to shake up their aesthetic without risking sounding out of step with the times. It’s like going trip-hop in 1996 or “IDM” in 1998 or dance-punk in 2002 or freak-folk in 2004 or chillwave in 2009 or synth-pop in 2011. And just like those trends, some of the music will stand the test of time while some of it will sound impossibly dated in just three or four years the same way bands that ripped off Merriweather Post Pavilion sound dated now. That’s not to say everyone experimenting with the sound is doing so cynically; Wye Oak’s Wasner has made it clear in plenty of interviews that she felt paralyzed by her band’s established sound and needed to follow her muse wherever it led her. Others might finally feel free to indulge impulses that once would have been wrongheadedly rejected as “guilty pleasures.” Still others might simply have heard Dirty Projectors’ “Stillness Is The Move” or Frank Ocean’s “Pyramids” and experienced a bolt of inspiration; after all, what is any creative endeavor if not a response to the creator’s environment?

Now that R&B more or less is the environment, though, its time as the underground’s de rigueur creative catalyst is surely nearing conclusion. It’s hard to imagine the indie-rockers who’ve come late to R&B in search of a creative jolt sticking with it as a long-term proposition once the freshness wears off, and some of the key initiators of the movement are already moving on. Look no further than How To Dress Well’s Tom Krell, whose latest single is closer to space-age soft-rock than the ghostly R&B he pioneered. His sound became the template for countless copycats, and rather than become calcified in that sound and risk disappearing into a SoundCloud of imitators, he is pressing on, leaving others to hammer his advancements into clichés. Abel Tesfaye, whose initial releases as the Weeknd felt so fresh despite feeling so musty, would be wise to forge a similar path lest his bleak, druggy sex tracks devolve into self-parody. He so thoroughly plumbed his aesthetic on his initial trilogy of mixtapes that by the time he got around to releasing his official debut album, he has exhausted the possibilities of that signature sound. These days the likes of Jeremih and Shlohmo are beating him at his own game.

This is how it always goes. Genre fads come and go, but each one contributes a few permanent fixtures to the festival circuit, stars who transcend their trend. We saw it happen with chillwave — the innovators moved on to new sounds and remained viable, and those who stayed too closely aligned with the sound of a passing moment were banished to obscurity. In this case, it seems likely that Ocean, Miguel, and Monaé will endure because their careers hinge less on the trend that lent them extra visibility than the timeless quality of their songwriting and/or performances. Solange and Blood Orange have established similar star power on an underground level. Others might manage to last, but if they do, it will be by virtue of the dynamism that made this wave of R&B feel so exciting in the first place. A kaleidoscope remains alluring only as long as it keeps moving.