You're a musician. You've built a pretty good solo career. All that you've achieved, the credit and the blame, falls on your shoulders. And you're okay with that.

Now, imagine that there are two other artists who've pretty much done it on their own, too. They seem like good guys, but you sense that you're on slightly different creative wavelengths.

Can three such people create something together that none of them might have done on their own? Will the egos they've built through years of being their own bosses get in the way?

Enter the Thorns, three musicians whose debut album on Columbia presents a whole that's greater than its sometimes mismatched parts.

Peter Droge — Northwestern roots rocker with ties to Pearl Jam. Matthew Sweet — New Yorker by way of Athens, Georgia, with one foot in jangle-pop and the other in punk. Shawn Mullins — army veteran and self-produced folksinger and songwriter. They had little in common, other than their catalogs of solo albums and the loyalty that each inspired from his fans. Even so, they all wound up one day in a room at Sunset Sound, the legendary Los Angeles recording complex, with a bunch of guitars and a vague sense that they ought to explore some kind of joint project.

All agreed, first of all, that no one would jockey for leadership or force the other two to rotate through moments in the spotlight and into the shadows of accompaniment. “We wanted to be a band, as opposed to three guys showcasing themselves,” Mullins says.

As for areas in which their musical styles might not intersect, those could be turned into powerful points of connection. “We were lucky,” Droge says. “If we were all too much the same, it wouldn't have worked. And if we were too different, it wouldn't have worked. But we had a perfect blend of similarity and difference, especially in our singing. Shawn obviously covers the low stuff, and Matthew's voice is one notch above mine.”

By embracing their dissimilarities, the trio found an approach to building an uncanny vocal blend. More to the point, harmony would form the heart of their union, and so they resolved to follow an unusual method for writing their material.

“From what I've read,” Mullins explains, “with CSN, CSNY, and the Eagles, someone would bring in a finished song and everyone would say, ‘Let's add the vocals.’ That's not what we did. We worked out our harmonies as part of our writing process, as each song was coming together.”

Picture this, then: On that first day at Sunset Sound, and during more protracted sessions at an isolated ranch north of Santa Barbara, the Thorns would strum and sing simultaneously, improvising lyrics as well as parts. They quickly found a way to fuse harmony to structure seamlessly — though not without some cost.

“Because we were singing as we wrote, our melodies wound up being very streamlined,” Droge says. “If I were singing some of these songs by myself, there would be more turns or little extra notes at the ends of phrases, or there might be more jumps in the melody. When you've got three guys hanging on to the tune and suddenly you have to jump over a big interval, it's hard for the harmonies to stay intact without rubbing against each other. But because the three of us devised our harmonies together, we made melodic choices.”

The same applied to the lyrics, which adhere to a familiar, life-and-love formula throughout The Thorns (Aware/Columbia, 2003). “We've all been singing long enough that, in order to adapt to a group sound, we instinctively refined our phrasing, as far as not being behind the beat or dragging a word,” Droge continues. “And since our phrasing was simplified, the lyrics were simplified as well.”

Perhaps the most important lesson here is that once a collaborative project like the Thorns' is wrapped up, the members of the group will come away better equipped to resume their solo efforts. “Since working with the Thorns, I've done some recording on my own and found that I miss the other voices,” Droge says. “I've been doubling my vocals now more than I used to, and Matthew has been doing that too. Also, I'd been doing a lot of underscore music for movies, which is music that's emotionally effective but not noticeable — the exact opposite of pop music, which you want to stick out and grab people's attention.

“On the other hand, a lot of the ideas I brought to the Thorns were harmonically and chordally very simple — I-IV-V stuff. Now I'm experimenting with more complex changes for my own music again, which feels really fresh to me.”