Trond Reinholdtsen is an eccentric's eccentric. He is not in any way edgy or abrasive, nor is he trying to be; he is simply and thoroughly weird, in the profoundest sense of the term. His website comprises three small hyperlinks beneath a picture he took of himself with what appears to be a front-facing laptop camera: he is making a strange face, his glasses are a bit crooked and he has two prominent zits, one near his left nostril, the other a bit above the right corner of his mouth. Reinholdtsen is often discussed in terms of enormous artistic vulnerability and risk, and it's not difficult to see why – he presents a remarkably uncalculated and raw musical practice, just like his homepage. Few musicians are either willing or able to take their total-artwork projects so far that the decorum of concert life and art institutions seems to come undone.

Reinholdtsen's multi-part digital opera Ø (pronounced like the rounded vowel found in several Scandinavian languages but referring to the set-theoretical notion of an empty set, if I'm not mistaken) was, for a couple years, talked about in the excited hushed whispers in which I remember hearing Wandelweiser discussed back in the early 2010s. In most circumstances, a YouTube opera series inspired by the philosophy of Alain Badiou would be bad; somehow, this isn't. It's as notable for its outrageously ornate costuming and puppetry as it is for its dramaturgy and sound. In fact, a truly contemporary, multidisciplinary opera-blob has been a remarkably enduring obsession for Reinholdtsen. His long-term anti-institution, The Norwegian Opra, has existed for over a decade, producing a series of projects that more closely resemble bizarre internet detritus than the usual products of new music – more Ratboy Genius than Donaueschingen. Indeed, the first video he published online, from 2009, is him watching Werner Herzog's Fitzcarraldo and imitating Klaus Kinski's cadences as he shrieks his demands for an opera house, followed by two seconds of him rolling around on the floor in a piece of green fabric. This is characteristic: Trond is less laser-focused than Patrick Frank, the other composer of his generation similarly possessed by an uncontrollable desire to explode the possibilities of new music, but he makes up for it in sheer unhinged inventiveness.

From what I can gather (as the website description suggests, professional information is a bit scattershot), this is the first commercial release of Reinholdtsen's music. Unsichtbare Musik, the A-side of this LP, is the earlier of the two pieces, dating from 2009. It was written for a concert broadcast live from the Berliner Philharmonie, taking radio broadcast as its organising principle to launch into ‘a kind of lecture where the composer guides the listener into what is happening… as the piece develops, of course, the information you get as a listener from the composer and what actually happens in the music becomes more problematic’ (Anders Førisdal, the guitarist of asamisimasa, in conversation with Matthew Shlomowitz on the podcast Soundmaking, episode 89).Footnote ¹ This has been a much favoured format of conceptual and postconceptual music from Tom Johnson's 1975 Failing onwards.

As is typical in the lecture-recital form, this is an archly self-aware bit of music-making. There are some bits with a succession of silly noises from silly sources that are highly reminiscent of Kagel at his most instrumental-theatrical (Zwei-Mann-Orchester, Staatstheater, etc.). The speaker himself namedrops Kagel alongside a couple of other not unexpected figures (Stockhausen, Lachenmann) before there is an extended section using a live recording of a Cage performance at the 1958 Donaueschinger Musiktage. Like every other European live recording of a Cage performance from the late 50s, it is nearly unlistenable owing to eruptions of laughter of the audience every time a sound event occurs. These were watershed performances for audience dynamics in new music: the more ambitious works by composers earlier in the 1950s generally elicited angry mumbling and passive-aggressive coughing (if there was laughter, it was breathless, haughty and incredulous), whereas post-Cage, audiences suddenly seemed to feel like they were in on the joke – that's when you get the self-satisfied art-house laughter. It's not clear which one Reinholdtsen is going for here. There's a bit at the end where the speaker says ‘kapitalistische Musik’ before samplers pump out some anodyne stuff on GarageBand factory defaults, which makes it seem like he's going for the latter, and his frequent turn to explosion SFX certainly seems to openly invite giggles.

But not all of the joke is so straightforward. Let's take the lecture-recital format favoured by conceptual music: it's a format that favours humour of an in-posturing, self-satire sort, whether that's the sidekick of Johannes Kreidler's Audioguide wearing a Porno Adorno T-shirt or the lecturer of Brian Ferneyhough's Shadowtime summarising Aristotle or Celeste Oram's Ted Wiesengrund delivering an austere bit of scholarship on fellow émigré Richard Fuchs in Tautitotito. At a basic level, the humour is self-evident, and the audience is in on it. On the other end of the spectrum is one of the most profoundly devised pieces I've ever encountered, Patrick Frank's Das Meisterwerk. Unlike almost all of the conceptual and postconceptual lecture-recitals, no-one could possibly be ‘in’ on the joke – it is for all intents and purposes a straightforward lecture recital. The only gimmick is hidden from the audience – when they are asked to vote on which fourth movement they would like to hear, ‘original’ or ‘simulation’, there is only one movement that will be played whichever the vote – and even if they were aware of it, this knowledge would avail them nothing: they still have to sit there and listen, even if they don't vote. Something like this not only pokes fun at the intellectual trappings of inevitably institutional music-making but claws at the knotted core of the art-music concert experience. Reinholdtsen is closer to Frank's ethos than straightforward performative jokes: at its best, this music reaches these dizzying heights of genuine bewilderment and cosmic humour.

Spätstil, in its recorded form as the B-side of this record, is even more explicit a radio drama. The premise is that asamisimasa has been playing Unsichtbare Musik again and again for quite some time: it is introduced by a now theatrically bored voice speaking the musical terms in German before a distorted voice, essentially the narrator, breathlessly monologues the performance history of Unsichtbare Musik, which, we are told, is a landmark of twenty-first-century new music. The narrator then moves on to what sounds like blog posts on new music in English, maybe something from Moritz Eggert run through DeepL. I make this comparison because while the voice is speaking in English, it is frantically reeling off preoccupations that no Anglophile musician I know of would refer to (the ‘post-Anthropocene’? ‘what is needed now is a music-for-itself’?), which makes the whole thing difficult to follow. There's more than a little overstimulation here, which is somewhat at cross purposes with text that is either didactic, parody-didactic or post-irony-didactic.

But that's fine, and that might even be ‘the point’, as it were, since the narrator then says something about moving from evoking circa 2009 nostalgia to the apocalypse of 2022. This announcement prompts the expected explosion sound effects (the narrator has also previously mentioned a ‘very loud sound’ which is a ‘metaphor’). Anders Førisdal describes this overture as Trond's farewell to a certain kind of performativity and ‘his self-presence’ in performance. That sounds about right.

What follows is a pre-recorded canonical-music collage reminiscent of several tape works by Georg Katzer or the output of the WDR's Studio Akustische Kunst. After a couple minutes of this shock-and-awe, the remaining 15-odd minutes of the piece could more or less be titled Indifferenz. It's nearly impossible to tell what asamisimasa are doing for large portions of Spätstil – there's a bit where they're groaning and making low-pitched squeaking noises, which lasts for a long time, but there are other squeaking noises that might well be superimposed sound effects, and there are significant sections where they're gone behind the phalanx of orchestral greatest hits. So they're not foregrounded in a conventional, virtuosic sense of performance, but, in reality, these works were realised for asamisimasa in a remarkably holistic fashion; on a dramatic level, Spätstil essentially functions as fanfiction. Indeed, a great deal of the ensemble's collaborations involve composers who similarly treat performance in an expansively multimedia/multidisciplinary and conceptually rich approach that emphases unity of gesture and affect. I'm thinking here of their portrait disc of fellow Norseman Øyvind Torvund, as well as a number of their concerts with music by Mathias Spahlinger or, especially, Bryn Harrison. It makes sense, then, that this music, so knottily concerned with pre-individualised sound, really precludes singling out isolated performances. In fact, the only part where I would be comfortable writing something about an individual performance in this recording is Morten Barrikmo's clarinet solo in Unsichtbare Musik, which manages to be both viscerally striking and detached, although this is, of course, itself a parody of soloistic performance.

And this is the ultimate uncomfortable balance with Reinholdtsen: on one level it's vibrantly intellectual and arcane, on another it's unserious in the most profound and goofy sense of the word. This is fun, challenging music. It is music that sticks in your mind and makes you want to return to it again and again. In its sheer persistence it is even rather poignant.