Fittingly, it’s easier to define them by what they aren’t than by what they are, given that their very name evokes a kind-of absence by design. Neither drawing-room prim or Gothic kitsch (see: Rasputina), their music — although not rock by any stretch — flirts with the same quiet/loud dichotomy first patented by the Pixies, and to equally stirring effect. Exploiting negative as well as positive space, the band shapes gripping music — sometimes out of thin air.

You can hear it on their self-released debut, My Invisible, but it’s even more pronounced during their vibrant live show, in which the blend of cello, violin, guitar, Roxy (an antique instrument), pick-up percussion, and intricate harmonies intertwine to create something that’s hard to pin down. Searching for influences, one hears echoes of the Slits’ percussive, ramshackle humor, of This Heat’s haunting complexity, of Dirty Three‘s sun-drenched expansiveness. And if that sounds complicated, embodying all sorts of seemingly contradictory impulses is part of My Invisible’s considerable charm.

Initially convened as a duo solely to play a Rolling Stones cover at a Brown University theater event, the group evolved briefly into a quintet called Television Astronaut before settling in as a trio consisting of Popahna Brandes on cello, Carolina Maugeri on violin and Roxy, and Miranda Mellis on guitar and percussion, with all three sharing vocal duties. Carolina recalls being asked to join at a Sonic Youth show: “[Initially], there was some sort of promise to play multiple instruments that we weren’t used to, and [play them] badly. I figured I could play the recorder or something.” Miranda adds, “It was also going to be this infinitely expanding collective that would never end. There used to be this band Polkacide. [When they played], other people would get up onstage [to play with them] — there was no clear boundary to the band.” Thankfully for us, My Invisible didn’t go the musical anarchy route, paring down to the essentials while still allowing for instrumental digressions. As Miranda says, “It found its own form.”

Which brings us to Roxy.

By some counts the band’s fourth member, Roxy is an Italian antique that found its way into the band mysteriously, a gift from a fellow musician. She looks like a tiny upright piano on tall, spindly legs, but sounds uncannily like an accordion. It wasn’t until well into My Invisible’s life that the strange instrument asserted herself. “We just didn’t have time for the Roxy. And then somehow she just . . . appeared. It was time to bring her out,” says Carolina. The Roxy is used sparingly, as an accent, but adds jauntiness to the song “Duplicity” and confers Old World elegance to everything else. Roxy may soon have company: Popahna has recently begun practicing a few songs on xylophone, and Miranda is determined to try the trumpet. Carolina adds, wryly, “If we ever bring in a piano I hope it’s an out-of-tune one. I like to work with disabled instruments.”

Not surprisingly, this is a group that welcomes, even accentuates, what some might consider imperfections —the pause for breath, the click of a tongue against the roof of a mouth — staccato, organic sounds that add to the humble surface allure of the songs. My Invisible’s seven tracks are part of an ongoing song cycle of conceptual tone poems, each reflecting a different state of being. “Receptivity” uses samples of Japanese children’s songs, plucked, pizzicato strings, mournful cello, and even the player’s breathing to build into a kind of gentle roundelay. Other songs — such as the fierce “Aggression” and the playful, painterly “Duplicity” — are less linear in construction, unfolding with narrative digressions one associates with prose writing.

Which makes sense, be¬cause all three members are writers who met through Brown’s Literary Arts program. (Mellis is also co-editor of local literary journal Encyclopedia, the first issue of which is due in June; go to encyclopediaproject.org f0r more information.) Accordingly, My In¬visible’s lyrics are as carefully crafted as the music, referencing sources as diverse as Adorno, Heinrich Heine, MC Lyte, and SF punks the Afflicted, with equal affection for all.

In live performance the band is less conceptual and more freeform in approach, constantly switching off on instruments, varying textures, harmonizing, and allowing for seemingly spontaneous “atonal band cheers.” From the sublime to the ridiculous and back again . . . My Invisible in a nutshell.

MY INVISIBLE + HUMANWINE + AMBITIOUS ORCHESTRA |  May 13, 2-5 pm  | AS220, 115 Empire St, Providence | 401.831.9327