San Francisco’s Sleepy Sun broke on the scene with 2009’s Embrace, an album of hazy psych rock that’ll often fly off the rails into something practically free-form before finding solace in an expert stoner riff that could easily be jammed on for eternity. Back then, the band was a six-piece, with dual vocal duties going to guitarist Bret Constantino and singer Rachel Fannan. The 2010 follow-up, Fever, was stronger, featuring more of Fannen’s soulful and powerfully haunting vocals, a welcome addition to the band’s already blossoming sound. Last year’s Spine Hits, however, is the band’s first album without Fannan, who left the band not long after the release of Fever.

Today’s 12 O’Clock Track, “She Rex,” is a straightforward psych-inflected rock ‘n’ roll song for the most part. It’s not till two minutes in, when the track slows to a crawl and the delay pedals are put to good use, that you really notice Fannan’s not around—the dirgy moments were her best because she could let her voice really stretch out. Constantino does an admirable job of approximating Fannan’s ethereal vocal quality, pushing into a high falsetto before coming back in strong with a fiery riff, but it’s tough to ignore her absence once you dig deeper into the album.

Sleepy Sun open for City and Colour on Wednesday at the Riv and headline a show at Beat Kitchen on Halloween, with Pink Frost and the Cairo Gang opening.