Two years after stirring up a murky swirl of psychedelic folk on Eucalyptus, Dave Portner sounds like he’s in a brighter mood on Cows on Hourglass Pond, his third solo album away from his day job in Animal Collective. The energy levels here don’t quite match the kaleidoscopic, kinetic overload of his group at their most madcap, but jangly guitars lend a cheerful air to songs like the breathless “Eyes on Eyes” and “Saturdays (Again),” while dub-techno beats (“What’s the Goodside?”) and inventive sound design (“Our Little Chapter”) find Portner continuing to push himself sonically. And as centerpiece “K.C. Yours” attests, his imagination has never been in sharper form: Set to a groove that’s both wistful and rollicking, the song vividly imagines a post-apocalyptic scenario in which robot overlords rule everything, even love.