With the hardcore kids all grown up and go-go frequently looking back, it might seem that nothing new is sounding in Washington. But right now, there seem to be more D.C. bands and artists playing challenging, thought-provoking music than ever before. And some of the best, most frequently rewarding ones are collected here on the fourth installment of District of Noise. It’s out just in time for the latest iteration of the Sonic Circuits Festival of Experimental Music, which begins Wednesday.

Leading this assault on easy listening is Jeff Surak, the soft-spoken but always ardent champion of Sonic Circuits. Since the first festival in 2002, Surak has continued to bring the brightest stars in the experimental firmament down to D.C.: Merzbow, Faust, Jandek, Matmos, Tony Conrad, Phill Niblock, Rat Bastard, and so on. But Surak the curator is also a creator called Violet; here his “Incapacitated by the Sun” is a steady, minimal drone, like one of Merzbow’s monoliths spiked with a nip of Mr. Bastard’s fuzz.

Meanwhile, Blue Sausage Infant’s “Gemüsemaschine” is pure kraut—-feisty, filling, and highly fermented. In his recent review of BSI’s first-ever long player, Negative Space (put out by Surak’s Zeromoon imprint, no less), City Paper’s Joe Warminsky noticed the same precision-engineering care of guests Jeff Barsky on guitar and the motorik percussion of Jason Mullinax. And since D.C. is kind of a small town, both Insect Factory (Barsky) and Pilesar (Mullinax) show up on District of Noise Vol. 4, as well. I’ve long sung praises of Barsky’s unique textures, and I’ve been nodding in assent to Mullinax’s jams since our college days at the University of South Carolina. That said, their contributions (“Slow Bloom” and “Spider Bait,” respectively) sound more deliberate, more mature than anything I’ve yet heard from them. As Surak’s festival programming confirms, experimental music has a canon now, and the work of Chester Hawkins (a.k.a. Blue Sausage Infant), Barsky, and Mullinax are gunning for inclusion.

Of course, experimental music is often precisely that. Many times, the results fail to yield anything qualitatively good. I could do without the forced collaboration of TL0741 and Anthony Pirog on “Busy Bees.” Individually, I like both very much (in fact, I’m quite eager to hear what Pirog does with Terry Riley’s indefatigable In C at this year’s festival), but this meeting does neither party any favors. Likewise, I’ve heard better from Pirog’s other partner in crime, Janel Leppin. To be fair, we don’t see any visuals from her “Music for a Film, The Recipe,” so it’s hard to judge too harshly. Then again, Music From the Film’s “Animal Friends” succeeds because it’s playtime narrative let’s us make up our own. After all, not all experiments are serious experiments.

It maybe be a little early to call—-like most releases of its ilk, the District of Noise compilations need time to percolate—-but I think Borborites’ “Sunrise in an Opium Den at the End of the World” is my favorite cut. There’s a forward motion to its tainted slab of synth and treatments that compels an active listen. Just as Thomas De Quincey learned to appreciate the subtleties of opium, there’s plenty of nuance to Borborites’ sun-baked apocalypse.