Zachary Cole Smith opens the door wearing a collarless white button-down shirt so big it could pass for a nightgown. The 28-year-old DIIV frontman is also rocking a leather ball cap over his light brown shoulder-length locks, plus baggy white shorts and black low-cut shoes with tall black socks climbing up his calves. Short, slight, and boyish in the face, he looks like a kid dressed up as a 19th-century baseball player for Halloween. It’s about 10 o’clock on a seasonably hot July Monday night. We are on the sidewalk in a vaguely defined area of Brooklyn between the heavily gentrified Williamsburg neighborhood and the increasingly gentrified Bushwick. Across the street in a warehouse decked out with colorful murals and gym mats, a group of men are breakdancing. Various musicians have been coming in and out of the graffiti-strewn brick structure Smith just emerged from, one of those industrial buildings where bands rent out space to practice. DIIV are borrowing a room from their buddy Matthew Molnar of Friends for tonight’s rehearsal.

“Sorry, the space is really small,” Smith says, leading me inside down whitewashed halls and identical doorframes. “Our drummer’s not here, so maybe you can sit there.” The space is really, really small — smaller than some people’s closets — so I press my back against one of the plain white walls while four out of five members of DIIV scramble to practice new songs. Also present: guitarist Andrew Bailey, a grade-school friend of Smith’s who wears blonde braided pigtails and used to play in gothic garage-rocker Shilpa Ray’s band the Happy Hookers; bassist Devin Ruben Perez, a skateboarder and devoted astrologer who’s never been in a band before DIIV; and guitarist/keyboardist Colin Caulfield, a veteran of various underground music projects who joined DIIV last year to flesh out the live sound. All of them are wearing baggy clothes with long hair streaming out from under their baseball caps.

Not present yet is drummer Colby Hewitt, formerly of Smith Westerns, who is off somewhere working on a photo project with his girlfriend, the acclaimed documentary and fashion photographer Sandy Kim. In Hewitt’s absence, his bandmates are attempting to play along with demos from Smith’s laptop using a click track, and the resulting racket is not helping anyone figure out whether these songs are ready for the road. Smith clicks around his iTunes library through innumerable recordings — some of them familiar to his bandmates, others not, most of them described as “that weird one.” This process repeats several times over: Smith plays a few seconds of one song, then another, then another, until eventually he stumbles upon the song he’s looking for. He intersperses his search with brief digressions about the influences behind these songs, referencing “the Television scale,” Weezer’s “Only In Dreams,” and one poppy new number that descends into “some weird Suicide jam.” At one point, he spends several minutes seeking out a track they’ve rarely rehearsed before. “I found it!” This is it! Let’s do this,” he says. “Or is that a waste of like one hour of practice?”

Smith doesn’t really have an hour to spare tonight. He and his bandmates are scrambling through what might be their only rehearsal for their first US headlining tour, which launches later this week. The goal is to road-test new material for the follow-up to DIIV’s 2012 debut album, Oshin, an underground breakout hit that marked them as one of indie rock’s most promising bands on the rise. Tomorrow he has to take care of countless logistical matters for the tour such as picking up borrowed gear and buying a van, which would be stressful enough for a random Tuesday. But tomorrow is also the 22nd birthday of Smith’s girlfriend, the model and acclaimed pop singer Sky Ferreira, and he needs to make it special after spending much of her 21st birthday stressing out about an impending European tour. “Last year I blew it,” Smith says. “She was so upset.” On top of all that, he’s also supposed to meet with his probation officer upstate, one of many unpleasant consequences of being arrested for heroin possession and other crimes last September in upstate Saugerties, New York.

Smith has decided not to go to the appointment in Saugerties and is crossing his fingers that he’ll be allowed to push it back. “I made a decision that I can’t go and that rehearsing and getting my shit ready for the show and being with my girlfriend on her birthday is more important than that,” he says. “My lawyer says that they should be able to postpone it, but we don’t know what their response is going to be.” To help make this happen, I’ve been asked to supply a letter on company letterhead explaining Smith’s commitments for this feature. It’s being forwarded to the courts along with the contracts for DIIV’s tour dates in the hopes that with enough documentation the authorities will take Smith’s commitments with the band seriously. “If somebody was like, ‘Oh, I have to work at the factory on Tuesday,’ they’d be like, ‘Oh, OK,'” Smith says. “For me, they’re like, ‘No!'”

The preeminent stressor of the moment, though, is band practice. There are so many songs to learn and so little time. DIIV are opening Ferreira’s benefit show for the David Lynch Foundation this Wednesday at the Music Hall Of Williamsburg, and the tour kicks off in earnest Thursday and Friday with two more sold-out headlining gigs at the same venue. “This is our first US headline tour, and it’s kind of crazy to be doing it not on a record,” Smith says. The main point of the tour is to workshop new material and move forward with the second album, so DIIV have to get some of that material ready for the stage tonight or else remain in between-album limbo. Still, Smith seems less concerned with the number of songs they bash out and more focused on satisfying his audience. “On this tour people want to hear new stuff, but nobody likes hearing new songs,” he announces to the band. “Nobody’s gonna want to hear us play the next record all the way through because they don’t know it.”

Technically, there’s no next record for people to know just yet. It’s not for lack of effort. DIIV recorded some material with JR White of Girls last summer, but the sessions were scrapped, and Smith returned to writing and recording DIIV’s music in isolation. He says he’s finished more than 150 songs in the two years since Oshin, and those are just the ones he still likes. Still others have been deleted or disappeared into the crevices of his hard drive. Many are saved under names like “Shitty Song” and ” Fuck You,” which doesn’t much help Smith remember which one is which. Smith presents the best of these creations to the band, supplying each member with a meticulously written part. Some of those parts are incredibly simple, to the extent that while rehearsing one song, Bailey can load up Yankees highlights on his phone with his left hand while jangling away on an open guitar string with his right. That’s just the way Smith writes — lots of independent bits and pieces that don’t amount to much on their own but, when deployed at the same time, fade into careening post-punk mirages.

After about an hour of middling results and a water-and-cigarette break, Hewitt shows up — also in baggy clothes and a ball cap, but taller than his bandmates and with close-cropped hair — and immediately DIIV’s new songs jolt to life. The heat is suddenly far less oppressive, whether due to the water everyone is chugging or the sense of lifting pressure as the new material comes together. These songs reveal a real diversity within DIIV’s carefully honed aesthetic: One song starts out dreamy, accelerates into aggression, then glides gracefully to conclusion. Another one is an instrumental post-rock slow-build that could almost pass for Explosions In The Sky. Yet another is ominous, noisy, and crushingly heavy from start to finish. DIIV spend most of their time tonight perfecting one song in particular, a brisk krautrock-informed joyride built around some of the most effortlessly pretty guitar lines of Smith’s career. Tentatively titled “Under The Sun,” it will make a marvelous lead single whenever LP2 finally emerges.

At the center of the swirl is Smith, more coach than dictator but definitely in charge. “Try and stay on the root notes and 4 and 5,” he counsels his fellow guitarists. “If we’re all on dissonant notes at different times it just sounds like a mess.” When posed with questions about the band, the rest of the members mostly just direct me to him. He’s DIIV’s founder and unquestioned alpha dog — the one who selects which song to practice, who stops the practice runs midway through and decides to circle back and try again, who notices when one of his bandmates’ instruments is out of whack and instructs them to tune up. At one point he even reaches over and twists Bailey’s tuning peg for him. Smith exerts control over DIIV down to the most minuscule detail, in part because he has carefully studied what makes music tick and how bands ascend from obscurity to maintain lengthy careers. In part, though, it’s because everything else always seems so close to going off the rails.

***

Smith was born in New York City to a musician named Zachary and a Vogue fashion editor named Debbie. That sounds glamorous, but any hope of an idyllic urbanite childhood fell apart pretty quickly. “They were old when they had me,” Smith says. “They had done their whole career and stuff. I don’t think my dad wanted to have kids, and my mom was like into her career and stuff. So they were like 35. They’d lived out their marriage. And as soon as they had kids, I guess it got super real for my dad.” The family moved to Connecticut when Smith was about 3 and his mom was pregnant with his younger sister. Smith’s father dropped off Debbie and little Zachary at a house they’d never seen and left for two years on tour. When he finally returned, he announced he was leaving for good. From then on, Smith went by his middle name, Cole.

Abandonment is bad enough, but being left behind in an unfamiliar place was especially rough for Smith’s mom, who loved living in New York but couldn’t afford it anymore as a single mother. Instead she was stuck raising two children alone, working six days a week at retail jobs she hated and living in a dilapidated house. “It felt like a shack,” Smith says. “It was this falling-apart, tiny, weird house that I spent my whole teenage years trying to rebuild and fix. I painted it, re-sided it, put all new doors and windows — like, basically rebuilt the house starting when I was a teenager until she sold it.” She dated a series of men, none of whom stuck. “My mom was almost a character out of a Helen Hunt movie,” Smith says. “She was a struggling single mom who just kind of hoped that she would land on a good space and somehow some miracle would happen to her.” She later married a man whose promises of financial provision didn’t pan out. “She couldn’t quit her job, which is all she wanted. She couldn’t even reduce her hours.”

Meanwhile, Smith was switching schools almost as often as he changed underwear. “I had disciplinary problems. Like, really bad,” he says. “I used to get in a lot of trouble in middle school and got suspended a lot. But then my freshman year, the very beginning of the year, like two months into the year I got expelled from public school. And my mom just didn’t know what to do with me at all because I was a completely out-of-control kid.” Untamed by his mom and stepdad, he ran wild for a year, skateboarding with friends and sneaking into school to mess with teachers. Eventually his stepdad stepped in and enrolled Smith at a private school, but before long he was expelled from there too. “I just loved when things would go wrong, like when the teacher wouldn’t be able to turn on the TV or something,” Smith says. “I just would do shit to make their lives difficult.” The process of enrollment and expulsion repeated several times over. School psychiatrists wondered if Smith was developmentally disabled, but he regularly earned high scores on aptitude tests such as the ISEE. “Nobody knew what to do with me,” he says. “I just underperformed so much.” Finally, after six schools in five years, he gutted out a diploma from the Wooster School in Danbury.

Throughout high school, Smith gravitated toward creative pursuits such as visual art and fashion. That’s when he started wearing humongous shirts, which he attributes to a combination of personal expression and shame about his physical appearance. “When I was in high school, I just felt really, really, really small,” he recalls. Smith’s mom would buy him XXXL shirts from her retail stores, and her friend would shorten the sleeves for him. He eventually learned to sew his own clothes, one of many hobbies that continue to this day. Here’s another: He collects rare coral reefs in a 50-gallon salt water tank at his apartment. “In a lot of ways, I feel like that’s who I am,” he says. “I’m a person who dresses kind of weird and just has some cool hobbies.”

Music was also a constant during Smith’s high school years. Becoming a musician had always appealed to him — and it frequently came up as a potential career on those aptitude tests — but he never considered it as a possibility until one of his mom’s boyfriends gave him a guitar during middle school. The fact that his biological father played music for a living (and in fact wrote the famous cotton jingle “The Fabric Of Our Lives”) never dawned on Smith growing up. “I never thought about it because we just never talked,” Smith says. “I didn’t talk to him for basically my entire life. We just only recently connected as adults.” As teenage Smith learned to play guitar, he downloaded a program called n-Track and started recording songs on the family computer. “I’ve always recorded on computers since then,” he recalls. “I could only think of music in a multitrack way.” Those self-taught methods have carried Smith far, though they also carry certain limitations: “I don’t really know chords. I don’t know songs. It amazes me when somebody can sit down and play an Elliott Smith song or something on guitar because I wouldn’t even know where to start.”

His mom insisted on college, so Smith chose Hampshire College in Amherst, Massachusetts because (a) he sensed there was a good sense of community there, (b) his uncle went there, and (c) it was the college “where it seemed like the most people were smoking weed.” In 2004 he enrolled at Hampshire to pursue a degree in studio art, his primary creative passion at the time. But even in the most liberal education environment imaginable, Smith despised school. “It’s like, wait, these people are paying $40,000 just to have a nice library and somebody who tells you what books to read?” he says. After his first year, he told his mom he wanted to drop out and follow the course syllabi on his own, but Hampshire beat him to the punch. “I ended up getting expelled from the hippiest hippie school in the world,” he laments. He now realizes that his anti-authority streak resulted in a lack of respect for the faculty, and just like in high school, he also struggled to connect with his peers. “The only people I fit in with were, like, the druggies,” he recalls. When Smith told his mom he didn’t want to do college anymore, she accepted the decision but also cut him off financially. “I’ve never taken a cent from either of my parents,” he says.