It’s not often that you come across a completely new and surprising format for live concerts, but that’s what Vienna artist, actor and director Oliver Hangl has come up with in the excellent series of “walking concerts” that he curates. The idea is simple, but brilliantly effective: the performer wears a microphone, the audience is kitted out with wireless headphones, and together they wander through the streets of the city, the singer serenading the audience as they go with music beamed magically into their heads. No need to worry about noise from passing cars, or that the music is too loud for the neighbourhood – there’s only you, your fellow audience members, the constantly changing environment and the performer, whom you can be as close to or as distant from as you wish. Every so often, the performer stops at an open space to sing and the audience gathers round. It’s a uniquely welcoming and intimate way to experience live music.

Hangl has put on quite a few of these walking concerts over the past couple of years, but last month’s event with Oliver Welter was the first I had attended. Regular readers of this blog will not need reminding of my admiration for Welter and his group Naked Lunch, and I remain stumped by the fact that no other writer in English seems to have cottoned on to their significance. Critical recognition is long overdue; in the meantime, Naked Lunch continue to impress with their wintry, melancholic alt-rock.

Anyway, this was my third time of seeing Welter solo. Following earlier outings at the Radiokulturhaus and the Chelsea, temples to state-sponsored culture and Anglophile scuzz respectively, here Welter and his guitar were to be found in and around the streets of Floridsdorf, the 21st district of Vienna. Kicking off on the steps of the town hall, headphones safely clamped over our ears, we negotiated pavements and pedestrian crossings before finding ourselves outside an Interspar supermarket. I really didn’t think we were going to go inside, but sure enough we did. Bemused shoppers looked up from their browsing as Welter launched into “God” from the Songs for the Exhausted album, its tone of savage pessimism sitting uncomfortably among the mops and buckets on display.

Our next stop, equally surreally, was a small funfair outside Floridsdorf station. Following a brief, tense period of negotiation between Hangl and a carousel operator, Welter – somewhat precariously, it must be said – took up position on the sweet little roundabout, whose young passengers were fortunate enough to catch the title track of the Universalove soundtrack album. Striding purposefully through the busy station itself, Welter delivered the first of several cover versions, Phil Spector’s “To Know Him Is To Love Him”. Here, as with later readings of Hot Chocolate’s “Emma” and Ike & Tina Turner’s “River Deep, Mountain High”, it’s Welter’s quavery, desolate voice and tender washes of acoustic guitar that turn familiar pop standards into expressions of forlorn, burnt-out romanticism.

Lighting out for the quiet residential streets behind Floridsdorf station, Welter answered my silent wishes with a stunning version of my favourite Naked Lunch song, “Military of the Heart” from This Atom Heart of Ours. The evening’s final setting, though, was as perfect as it was unexpected: a quiet riverside restaurant on the shores of the Alte Donau. The sun having long since set, an inky gloom descended as we stepped gingerly onto the jetty. After tearing his way through All Is Fever’s epic showstopper “The Sun”, Welter, in an inspired move that did more than anything else to make this event unforgettable, clambered aboard a small boat and proceeded to give the rest of the concert from there. Floating on the dark waters of the Alte Donau with a helmsman at the wheel, Welter’s anguished rendition of “The Retainer” was a heartstopping moment. As, indeed, was the evening’s last song, the despairingly bleak “The Funeral”, sung a capella by Welter as he and his craft drifted slowly out of vision and into the enveloping blackness of the night.

With the release of their 2013 album All Is Fever, Naked Lunch seem to have finally laid to rest the film and theatre projects (Universalove, Amerika, Ecce Homo) that they have been working on for the past few years, and begun to concentrate instead on cementing their unarguable position as Austria’s finest rock band. And not before time, one might add, since although those projects (Universalove in particular) had plenty to recommend them, as a body of work they didn’t really stack up against the group’s two full-length masterpieces, Songs for the Exhausted and This Atom Heart of Ours. So it was a great pleasure to see the band play a sold-out gig at the Arena in March, which I’m only now getting around to reviewing following their free show at the Museumsquartier summer opening.

I’m still struggling to get to grips with some of the reasons why I love Naked Lunch so much. I think it’s related to endurance, the idea that here is a group of people that has undergone extremes of experience and whose songs embody those extremes in a very direct and affecting way. I’ve never quite been able to banish the thought, for example, that singer and principal songwriter Oliver Welter was homeless for a while during the group’s five-year hiatus; nor that founder member Georg Trattnig died of an alcohol-related condition (“will it ever stop to hurt/will I ever wash away my pain”, as Welter sings on the elegy for Trattnig, “King George”). Yet what comes over so strongly now, in the group’s songs and performances, is a sense of triumph at having faced down these demons and come out, battered but alive, on the other side.

None of which would mean very much at all if Naked Lunch’s songs weren’t so lyrically passionate and melodically resplendent. Now tracing skeletal, desolate melodies (“Colours”), now launching into bursts of urgent riffing (“God”), the group display an exquisite flair for the immediate and the dramatic. Electrified by devastating choral harmonies, the songs depict traumatized states of mind (“there’s too much violence in my dreams/there’s too much hate running in my veins”, Welter laments chillingly in “Town Full of Dogs”) even as they clutch desperately at purification through sexual betrayal (“I did it with my best friend’s wife/it felt like paradise”). Yet there is tenderness and optimism as well, in the gently enveloping warmth of “In the Dark” and the radiant intimacy of “Military of the Heart”.

Bringing this quest to the forefront of the group’s activity, Welter is an immensely spirited and likeable frontman. Whether engaged in manic dancing, swaggering around the stage, trading moves with bassist Herwig Zamernik or inciting the audience into ever more energetic responses, he’s impossible to ignore. So too is the stunning coup de théâtre during “The Sun”, in which tiny shards of gold paper pulsate above the audience’s heads. And so too is the way the four men line up for the encores, bringing the shows to an end in an atmosphere of togetherness that is as celebratory as it is moving. We shine on together, when we walk hand in hand.

I was hoping this would be a proper Naked Lunch concert, but unfortunately it didn’t turn out that way. What we got instead was a kind of showcase for their latest project, soundtracking a new theatrical adaptation of Franz Kafka’s novel Amerika. The full production is currently underway in the group’s home town of Klagenfurt; I’m not sure what the deal there is exactly, but I assume they’re playing along to the action much as they did when they performed their live soundtrack to the film Universalove. Those of us in Vienna will have to make do for now with this curious hybrid, at which the group performed only the nine songs from the play, accompanied by a cast of walk-on guests and preceded by a lengthy reading from the novel.

It was great, of course, but it was also a touch insubstantial, and I really hope that after this second successive audio-visual project Naked Lunch get back to being a rock band again. It’s been four years since their last masterpiece This Atom Heart of Ours, and a new album consisting of full band versions of the new songs Oliver Welter premiered at the Radiokulturhaus last year is sorely awaited around these parts. A brief word with Welter after the gig confirmed that such a thing is on its way later this year.

Anyway, tonight’s performance confirmed my long-held view that Naked Lunch are a highly creative outfit with a spiky and uncompromising approach to songcraft. The opening song of the piece, “Let Me Walk Upon The Water”, sets the melancholy tone, with Welter’s haunting and troubled voice framed by Stefan Deisenberger’s desolate keyboard melody. “Fight Club” sees the group hit an angry and convulsive seam, Welter’s vocal swelled by urgent choral backing.

It’s that razor-sharp interplay between voices and instruments that makes this music so compelling, and this was never truer tonight than on “The Tramp”, with its smart lyrical flourishes and impertinently perfect chorus. I have no idea if the English-speaking world will ever wake up to the brilliance of Naked Lunch. As I’ve said before, though, their loss is very much Austria’s gain.