A song isn’t necessarily “finished” just because it’s been recorded; any producer will tell you that the mixing is what really makes a record. Subtle tweaks and shifts in emphasis can bring new tones to a recording; a new instrumental backing might place the song in a different context altogether. Smart artists know this, and use remixes to explore differing shades of meaning in their work.

It’s the right strategy for the times. The de-emphasis on The Album as a cohesive whole, as a side-effect of the shift to digital content, means that The Song is again king — creating a climate where, say, LCD Soundsystem can release five radically dissimilar versions of “All My Friends” simultaneously, each with a particular emotional affect, without having to commit to any one of them as the “definitive” version.

It’s liberating for the artist, keeping your options open like that, but it’s a fraught position. There are a lot of choices to make, and things can go wrong as easily as they go right. And these choices are difficult enough for a living artist, still in the process of building a catalog; how much more so, then, for an artist who is no longer with us, and whose extant recordings have become a part of the cultural canon? How do you take something that is already complete, already definitive, and make it new again?

Now take those questions and multiply them by a factor of Johnny. Fucking. Cash.

On Johnny Cash Remixed (Compadre Records), released this week, a number of producers —including Pete Rock, Teddy Riley, and Mocean Worker — tackle what seems like a fool’s errand, not so much by remixing per se; rather, they drop Cash’s vocals into new and diverse musical settings.

There’s nothing inherently wrong with the approach, and it’s certainly not new. I have in my collection a curious little record called Swing It Lightly, credited to Django Reinhardt and Guitars Unlimited, bought on secondhand vinyl. The tunes were assembled by taking Django’s solos, recorded mostly in the 1940s, and mixing them to backing tracks recorded in 1968 — fifteen years after the man’s death. It sounds like a mess, but it’s a marvel. The tracks are scored for five guitars plus rhythm section; listen to how the arrangement of “Night And Day” (download) integrates Django’s lead lines into a bed of dense, shifting chords, often breaking out into startling harmonies. The purists sniffed then, and still do, but Swing It Lightly is tremendous fun.

More recently, Elvis Presley, the Beatles, and other classic rockers have been subject to the remix treatment. Whatever the artistic impulses behind these projects — and some have been more artistically successful than others — they serve the important purpose of keeping the brand alive, of declaring in no uncertain terms that this music is of more than historical value. They take rock ‘n’ roll out of the museum and took it back to someplace where you can feel it in your hips, just as you should.

Cash, though … Cash seems different, somehow. Here’s a man whose voice and image are more than just canonical — they’re downright iconic. His were perhaps the most instantly-recognizable pipes in pop music; if God doesn’t sound like Johnny Cash, then He damn well should. Now how do you take that voice, its every syllable sounding like it’s carved in granite, and turn it into clay for crafting something new?

Judging by Johnny Cash Remixed, you mostly do it by treating the original Cash tracks as an afterthought. On the lead single “Trail To Mexico,” (download) the remix team Mexican Institute of Sound treats Cash as an instrumental element, burying him behind the all-crushing drums and treating his vocal with a whiplash panning effect. The mariachi horns make a backhanded reference to Cash’s own “Ring of Fire,” which is sort of clever, I guess. It’s definitely irreverent, which is fine; the problem is that it’s not actually any fun. In fact it’s a chore to listen to, what with everything being in different keys and all. It sounds like a radio picking up two stations at once, like a failed mash-up, like musique concrète — like everything except what it’s supposed to sound like: a Johnny Cash song you can dance to.

Other tracks are less ridiculous, but not much more successful. Snoop Dogg (who executive-produced the disc) takes on “I Walk the Line,” serving mainly to remind me that Snoop Dogg is still alive, and the track somehow manages to sound more dated than the 1956 original. Digging deep into the catalog, Alabama 3 do what they do best on “Leave That Junk Alone,” creating a grimy, spooked, wonderfully sleazy dance track. But in the end, it’s more or less an A3 song, albeit with a prominent Cash sample; rather than shedding any new light on Cash, it instead showcases what a terrific band Alabama 3 are. Which, y’know, I already knew.

So yeah, it’s uneven, to say the least. The most successful tracks, perhaps not surprisingly, are the ones that play most to Cash’s established strengths; the Philip Steir remix of “Get Rhythm,” in particular, keeps the vocals hot and lively, slicing and dicing the tune over a pulsing electro track with popping bass, funky guitars, and a timbale breakdown. What Steirs remembers — what too many of the producers here forget — is that for all the weight and power of his voice, Johnny Cash could swing like a sonofabitch. That boom-chicka-boom guitar, always pushing the beat, was essential to his sound; when you tether his voice to the hard hip-hop four, something is irredeemably lost. For all that he atomizes and reassembles Cash’s vocal line, Steir finds the magic in the phrasing — and so, ironically, he more than anyone else here lets Johnny Cash be himself: Johnny. Fucking. Cash.