The merger of rock and jazz has never been as clear-cut as all that, kids. How could it be, when trying to make two such rich, diverse traditions work together? This week demonstrates how complicated the marriage can be, with three different approaches to the same basic idea.

Friday, Jan. 18

The recent history of pianist Eric Lewis is the history of ELEW, and it turns out that that history is already so rich—-so replete with human meaning and struggle—-that it’s hard to know where to begin with it. Lewis first made his mark in jazz as a Thelonious Monk Competition winner, then as the pianist for Wynton Marsalis—-gigs in which an in-depth knowledge of all jazz tradition is crucial—-but even with that splendid resume he found it hard to build a career. Figuring he had nothing to lose, Lewis decided to explore new possibilities; he decided to tackle rock, in his own way: as a solo jazz pianist. It involves transferring power guitar chords and violent vocal attacks and drumrolls to the piano, and applying jazz instrumental and textural techniques to rock staples. He calls it ROCKJAZZ, and to distinguish himself from the Eric Lewis of his former career he goes by the name ELEW. In a recent interview he named a place that nurtured him in that difficult and rather contentious transition: “There is a club called HR-57 in D.C. that kept me working[.]” And they nurture him still. ELEW performs at 9 p.m. at HR-57, 1017 H St. NE. $25.

Tuesday, Jan. 22

Jazz fusion didn’t go the way that Spectrum pointed. Drummer Billy Cobham‘s 1973 debut album, while rhythmically complex and powerful, suggested a bluesier, grittier direction for the jazz/rock blend that characterized the 1970s. The record’s guitar work even presaged the arena-bound heavy metal solos of the ’80s. Again, though, that didn’t happen for the fusion players; instead, they became gradually more taken with studio gimmickry and their own chops, the music becoming ever glossier and more self-indulgent. Still, 40 years after the fact, Spectrum stands up as a unique musical vision, a personal masterpiece that is one of the surviving pillars of the era. Indeed, it remains an important enough fusion touchstone that Cobham is making a tour of the album’s 40th anniversary. He’s a better, more able drummer now, and will doubtless bring that renewed virtuosity to the amazing music of Spectrum. Billy Cobham performs at 7:30 p.m. at The Birchmere, 3701 Mount Vernon Ave., Alexandria. $35.

Wednesday, Jan. 23
There’s rockjazz, and there’s fusion, but what about “lungcore”? The latter is a genre based in heavy metal, but featuring a line of horns (three saxophones and a trumpet) that riff and interact and improvise with the language of avant-garde jazz—-and maybe a little bit of punk-funk thrown in for seasoning. This genre, by the way, so far consists of exactly one artist: Jerseyband. The New York septet (also featuring guitar, drums, and bass) has, as you would expect, a crunching, thunderous sound with the kind of screaming vocals that are associated with death metal. As such it’s the one band playing D.C. this week that’s most likely to challenge ideas about genre and the distinctions therein. Is Jerseyband a jazzy heavy metal band? A metal-infected jazz band? A seamless hybrid? Or are there plenty of seams? Puzzling it out is part of the fun. Jerseyband performs at 8 p.m. at Atlas Performing Arts Center, 1333 H St. NE. $25.