Few things seem less rock than the idea of a rock band spending time carefully curating its online presence. (To be fair, very-rocking rock band Idles regularly posts absurdist reviews of chocolate milk to Instagram, and — other than maybe pictures of toppled-over electric scooters — it’s possibly the most rocking use of the medium we could ever hope for.) Updating Facebook, explaining lyrics on Genius, posting thinkpieces to Medium — the online upkeep and not-so-glamorous social media sausage-making behind building a following today just isn’t what I like to picture when I think of what a rock band is doing between touring and recording music.

Fortunately for my silly and very particular imaginary demands, rapidly rising noise-makers Black Midi basically don’t exist online. And still, they’re riding a colossal wave of buzz into South by Southwest 2019. Save for a sparse Facebook page (I’d wager a concession required of their recent signing to Rough Trade) and rave reviews that come up as search results, this young four-piece has built a following with nearly zero online presence. Looking to stream their music? Good luck. Heck, most of their songs don’t even have titles (not ideal for SEO purposes — the label must be ecstatic).

As for what those untitled songs are about? Beats me. I maybe caught all of three decipherable words (I’m 90 percent sure I heard “I”, “69”, and “look”) being sung or screamed from Black Midi’s two vocalists during their set Tuesday night at the British Music Embassy at Latitude 30. While slurred Mark E. Smith vocals may have made the lyrics mostly indecipherable, what came through loud and clear was that for fans of a certain sound, Black Midi is a rare thing of beauty — chaotic guitar noise held together by a foundation of phenomenal drumming.

Black Midi veered between laser-precision and a big ball of violence, a cartoon dust cloud brawl tumbling head over fist toward the edge of a cliff.

It was noise as jazz. A splatter painting of notes with math rock complexity kept on the rails by some explosive and tempo-shifting drumming with D.C. hardcore bass; freight trains of feedback and streaks of guitar static; and a vocal recording from a smartphone played through guitar’s pickups.

At moments it reminded one of Sonic Youth or Talking Heads or Lightning Bolt. It’s hard to put a finger on what you’re hearing, but it's brainy, brutal stuff not for the faint of heart listener — the stuff I jokingly refer to (for friends with lighter NPR indie tastes) as “nightmare music.” Think: a heady experimental jazz album being played simultaneously over Swans.

Black Midi takes their name from an obscure sub-genre of MIDI music where the keyboard is inundated with a humanly-impossible-to-play amount of notes at a break-neck pace, taking a relatively primitive-sounding instrument and creating a bizarre kaleidoscope of sound. While Black Midi say they just liked the name and nothing more, there’s a bit of a parallel to the intricacy on display and the balance between orchestrated patterns and pure cacophony.

Black Midi play again at 12:15 a.m. Wednesday night (technically early-early Thursday morning, but you knew that) at Barracuda Backyard.

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