San Francisco-based Dirtybird and Mothership impresario Claude VonStroke (a.k.a. Barclay Crenshaw) is one of the few electronic music producers who can inject humor into his tracks without coming off like a doofus. On his follow-up to 2006’s Beware of the Bird, VonStroke balances levity with darkness, as on “Monster Island,” where a madcap 303 whoop contrasts with percussive, jangling chains and hazy strings. Sometimes things dip into silliness (guest vocalist Bootsy Collins’ lyrical shenanigans on “The Greasy Beat,” the Detroit Grand Pubahs-esque boob homage “Big n’ Round”), but overall Bird Brain stakes out distinctive territory among tech-house’s most eccentric proclivities, Carl Craig-esque Detroitisms, lascivious Dr. Dre tributes, and Raymond Scott’s Soothing Sounds For Baby.