Chicago producer Robert Armani has been making some of the most arresting acid techno in the world for nearly 20 years. His tracks are marked by urgent rhythms, ox-stunning 4/4 beats, and that Roland TB-303 croak that can seemingly modulate in infinite variations. There's something archetypically Midwestern about Armani's tracky tracks: They're stoic yet ecstatic, all business in their desire to give you robust pleasure.

I haven't heard everything in Armani's expansive catalog, which includes releases on labels like Djax-Up-Beats, Tresor, and Dance Mania, but what I have experienced makes a beeline for that peak-time zone when the effects of the drinks, drugs, and people's biorhythms all seem to be culminating in a mass hands-in-the-motherfucking-air celebration. Dude's output isn't exactly subtle, but, damn, it gets the job done with admirable single-mindedness. And with "Circus Bells" (the Hardfloor remix, but still...), which I first heard on Laurent Garnier's X-Mix-2: Destination Planet Dream and which instantly blew my mind, Armani has created one of the most distinctive techno anthems ever. The man ain't clownin' around. Kudos to the Knightriders crew for booking this Windy City heavy hitter.

On a very different tip, the Tectonic Plates Vol. 2 compilation delves into dubstep's latest evolutionary developments, thanks to thoughtful curatorship by Tectonic label boss Rob Ellis, aka Pinch. Martyn's "Yet" kicks off the disc with brisk, springy beats, taking dubstep into lighter, less claustrophobic territory than it's typically occupied, but it still has that hyperalert, stealthy feel common to the genre. 2562's "Kontrol" slows the tempo to a sexy, supple skank, but retains a Burial-like desolation at its core. Skream's "Trapped in a Dark Bubble" unveils the ominous mood and methodically sadistic beats that made many warm to dubstep's cold, calculating heart way back in the mid '00s. Benga's "Technocal" is both a good neologism and an exemplary piece of hurly-burly rhythm science and gothic gloom. Joker's "Untitled_Rsn" brings a weirdly warped, electro-tinged nerviness to dubstep. RSD's "Forward Youth" eerily sounds like Bauhaus's "Bela Legosi's Dead," revamped and sexied up for the 21st century.

Ultimately, Tectonic Plates Vol. 2 represents an important document in dubstep's rapid mutation, a snapshot of the genre's top artists who are sparking off in many directions. In some vague way, it reminds me of Mo Wax's Headz comps, on which producers from various electronic genres converged in a shared zeal for the freshest expressions of their particular niches.

(Tectonic Plates Vol. 2 also comes with a Pinch-mixed bonus disc, which the label didn't send.)

Robert Armani, Jimmy Hoffa, Travis Baron, Grindle perform Sat July 4, Baltic Room, 9 pm, $10 before 11/$13 after, 21+.