The problem with Frank Black is exemplified by the very existence of his two new albums, Black Letter Days and Devil's Workshop. Black dissolved Pixies in 1993, in part because the band's tightly played, dynamic song style had become too confining for his rapidly developing obsession with surfing and science fiction. The man formerly known as Black Francis and Charles Thompson subsequently recorded and released six albums, leaping from beach music to new wave to heavy metal and back to punk. Now, for his seventh and eighth projects, he's cranked out 29 tracks of country-influenced rock, divided roughly into the raw (Devil's Workshop) and the mellow (Black Letter Days). The past decade's sheer volume of not-always-rewarding songs has made Black tough to digest. Both of the new albums were recorded live with a two-track recorder and have the quality of demos, with a few promising ideas waiting for a forceful collaborator to turn them into actual songs. But while Black's Pixies bandmates had distinctive musical personalities, his current backing group, The Catholics, merely supports him instead of pushing the music in any particular direction. Devil's Workshop is the shorter of the two discs, and the better by virtue of brevity and energy. The rollicking opener "Velvety" and scattered other punchy tracks ("Modern Age," "San Antonio, TX") display the casual hookiness to which Black has always had access. But these and the few other bright spots on Devil's Workshop and Black Letter Days primarily hint at what the albums could have been had Black made more of an effort. Usually, when a musician releases two half-baked albums at the same time, critics say he'd have been better off combining the best material from each and making one good album. But there's not enough worthy stuff here to assemble something sensible. Typical of both albums are songs like Workshop's "Are You Headed My Way?" or Days' "Jane The Queen Of Love," which each consist of a forgettable riff, a banal central phrase, and a few minutes of uninspired vamping. The tossed-off quality of his recent work may be liberating to Black, but it's not likely to be so satisfying to his audience.