The problem with the word “world” is that we tend to imagine everyone is looking at the same one. Igor Ballereau’s "UMWeLT" quietly objects to this arrangement. Borrowing its title from Jakob von Uexküll’s notion of the subjective environment inhabited by every living being, the album proposes something considerably more unsettling than an ambient record: four pieces in which perception itself seems to have become unstable, as though the walls of reality were made from a substance that could soften whenever nobody was paying attention.

Ballereau is an unusual figure in contemporary music because his earlier work was deeply connected to the voice, including compositions built around the letters and diaries of Lewis Carroll, Franz Kafka and Katherine Mansfield. His trajectory has nevertheless never been particularly interested in staying inside a single institutional definition of composition. After years of writing for ensembles and vocalists, a long silence eventually led to a new phase in which acoustic and electronic materials, darkness and enchantment, composition and the imagined cinema began to overlap. "ijkl" and the seventy-minute "Ptyx" opened that territory; "UMWeLT" goes further by making the territory itself increasingly difficult to locate.

The four pieces are long enough to resist the usual attention economy but not so long that duration becomes a test of moral character. “Umwelt - i” lasts twelve minutes, and its development feels less like a sequence of events than a gradual alteration of conditions. Sounds emerge without necessarily presenting themselves as objects. Something might resemble a voice, a room, a mechanical vibration, a distant environmental disturbance, but just when the ear thinks it has identified the source, the music changes the rules. Ballereau is not particularly interested in giving the listener a comfortable answer to the question of what exactly is being heard. This is less field recording than field hallucination.

That distinction matters because "UMWeLT" is full of traces. The album uses fragments of room ambience, playground sound and indistinct human voices, but their function is not documentary. They are evidence without a crime scene. A murmur may suggest another person; a familiar acoustic space may suddenly feel inaccessible; a human gesture can be reduced to texture and still retain some stubborn residue of intention. The result is strangely intimate without ever becoming confessional. We are not being told someone's story. We are hearing what might remain after the story has disappeared.

“Umwelt - ii” is especially effective in this respect. Its apparently porous environment continually allows sounds to enter and recede, while the piece maintains a remarkable sense of enclosure. There is no conventional melody to hold onto, yet neither is the music formless. Ballereau shapes density, distance, recurrence and disappearance with the precision of someone who knows that silence is not the absence of information. Sometimes it is the most suspicious information available.

This is where his earlier experience with voice becomes perceptible even though "UMWeLT" is not a vocal album in the conventional sense. Ballereau has spent much of his compositional life investigating language and the physical presence of voices, and here the human voice has been stripped of its semantic privileges. What remains is breath, grain, proximity, interruption. A voice no longer needs to tell us what somebody thinks in order to remind us that somebody was there. It is almost perversely effective: after centuries of teaching voices to speak, music discovers that they can be more mysterious when they stop cooperating.

“Umwelt - iii” deepens this sense of unstable recognition. The sonic material seems to circulate rather than progress, but repetition never quite produces reassurance. A sound returns altered by everything that happened around it, so that memory becomes less like retrieval than contamination. The piece has the peculiar sensation of listening to an event through a wall, then discovering that the wall is inside your head. This is not horror in any conventional cinematic sense. There are no monsters jumping out of cupboards, largely because Ballereau understands that cupboards are already quite psychologically complicated.

The final “Umwelt - iv”, stretching beyond thirteen minutes, gives the album its broadest temporal field. By this point, the listener has stopped expecting conventional development and begins noticing smaller shifts: changes in pressure, spectral colour, the distance between sounds, the appearance and disappearance of almost-recognisable presences. The music becomes compelling precisely because it refuses to convert these changes into obvious dramatic gestures. Its drama is perceptual. You notice that the room has changed before you can explain how.

There is a strong connection here with "Ptyx", which Ballereau described as music for imaginary films, but "UMWeLT" seems to remove even more of the cinema. There are fewer obvious postcards, fewer recognisable places, fewer clues about where the listener is supposed to stand. Instead, the album behaves like the soundtrack to a film whose camera has been left somewhere unattended while the world continues without it. The imagined narrative remains, but only as pressure.

Ballereau’s long-standing interest in literary documents is also transformed into something more abstract. Where letters and diaries once supplied words, personalities and histories, "UMWeLT" works with the remains of presence itself. Its sounds feel as though they have passed through an imperfect archival machine. Nothing is reproduced completely. Everything arrives slightly damaged, blurred at the edges, carrying an intensity that seems to belong to something no longer accessible.

That may be the album’s most affecting quality. It does not romanticise disappearance, nor does it attempt to reconstruct whatever has been lost. Instead, it pays attention to the peculiar life of the trace. A sound can survive its source without preserving its meaning. A voice can remain after the speaker has vanished. An environment can continue to exist while becoming completely different to the person who once inhabited it. The four pieces keep circling this paradox without resolving it, which is precisely why they feel alive.

"UMWeLT" is therefore not music that asks to be “understood” in the conventional sense. It asks the listener to surrender the assumption that perception is a neutral activity. Every sound arrives from somewhere, but the somewhere changes according to who is listening. Ballereau constructs that uncertainty with extraordinary restraint, allowing electronic tones, acoustic residues and human fragments to form a private ecology in which nothing quite stays where it was first encountered.

There is no grand revelation at the end, and thankfully so. The album leaves something more elusive behind: the suspicion that reality may consist less of stable objects than of temporary agreements between things, senses and memories. We hear a trace, decide what it might be, and for a moment inhabit the same world as it. Then the sound changes, and so does the world.