Mark Kozelek, aka Sun Kil Moon, can be as enigmatic as his music is sublime.

The creator of delicate, lyrically nuanced songs like Carissa (a heartbreaking tune about his second cousin burning to death) or The Possum (in which existential revelation arrives from the sight of the wounded creature) requests to be interviewed via email, and the tone of his answers veers from abrupt to completely dismissive to (once or twice) bizarrely courteous.

At one point he calls me a “good guy…you come from a good place,” but at another juncture he flatly replies “nothing of what you are talking about are questions that run through my mind, ever.”

Part of the problem is that Kozelek is reluctant to – or, as he would have it, incapable of – elaborating on his songwriting method, whether in the case of the aforementioned largely acoustic Sun Kil Moon work, or the heavier tones of this year’s collaborative album with experimental act Jesu, who joins him on stage at Concorde 2. Kozelek’s material – from his roots in indie outfit Red House Painters to the music he puts out under his own name – has enjoyed much critical acclaim.

“I appreciate your interest in the songwriting process, but for me, I roll out of bed and write songs. That’s it. I can’t elaborate on the process.”

There seems little doubt he is being honest, rather than merely lacking the inclination or motivation to explain his art. When asked how he connects seemingly innocuous events – such as the sight of the injured possum – to profound thoughts about life and death, he gives a similar response.

“I saw a wounded Possum on an Easter Sunday. A song unravelled from there. That’s it.”

Sun Kil Moon’s album with Jesu also features indie icons such as Will Oldham (aka Bonnie Prince Billy), and members of Low, Slowdive and Modest Mouse. “Going into details about how I met a person isn’t very important,” says Kozelek. In comparison to this crowded house approach, can the recording process for his solo material be a lonely experience, especially when Kozelek is so frequently searching inwardly for lyrical motivation?

“Recording and writing is when I’m most at peace,” he says. “Being alone doesn’t necessarily mean ‘loneliness’ in a negative sense. Being alone is crucial to being a writer. I don’t look in any direction for lyrical motivation. That sounds strategic. My songwriting is me, being me.”

It’s a point that Kozelek repeats often enough, but, again, it is difficult to argue against a man who claims – enviably – that his music comes to him completely naturally and without overthinking. This instinctiveness is what Kozelek enjoys about collaborating.

In the case of the Jesu link-up, he “responded to what was presented to me. I always go with my first instincts when hearing a piece of music.” While to some extent Kozelek’s email answers can be described as direct rather than necessarily truculent, there have been instances in his recent past of needless spitefulness.

After US rock band The War on Drugs’ set at a festival bled into Kozelek’s performance on a nearby stage, he railed against the group, calling their music “beer commercial lead-guitar shit” before writing a thoroughly distasteful and crudely-titled diss track.

Last year, music journalist Laura Snapes said Kozelek called her a “b****” (among other slurs) on stage at The Barbican after she tried to approach some of his peers for a big feature on the singer.

Even amid such a strongly-worded and unprovoked tirade, it is difficult to tell whether Kozelek is genuinely coming from a place of anger and bitterness or just practicing his own strange version of rebellion against the music machine and the media. Or both.

“Better stop before I make Pitchfork headlines for myself again,” was Kozelek’s joke after the Barbican incident. It is tempting to wonder why he agrees to do interviews at all in the light of such apparent mockery of the music press.

That said, Kozelek signs off his email to me in a seemingly genuine, friendly way – “all of my best!” – and some of his responses are more light-hearted than confrontational. Such as when I ask what the criteria is between releasing music under his own name and that of Sun Kil Moon. “There is no ‘criteria’ other than I’m hungry and am going to cook some potatoes and eggs right now.”

There can be little excuse for some of Kozelek’s public antics, but his tender, intuitive music cannot be denied. To anyone trying to reconcile these two sides of the man…well, good luck.

Sun Kil Moon & Jesu, Concorde 2, Madeira Drive, Brighton, Monday, September 19, 7.30pm, £28, 01273 673311