Throughout the 2010s there has been something of a renaissance in Brian Eno’s body of work. Granted, we live in an age of comebacks, revivals and reformations, but that’s a much more difficult prospect when it comes to crafting ambient music. For one thing, ambient music tends to be more of its milieu than any other genre, articulating structures of feeling – ways of experiencing space and time – that are minutely and exquisitely historicised. Nobody listening to any of Eno’s classic ambient albums from the 70s and 80s – Music for Airports, Music for Films, On Land, Apollo: Atmospheres and Soundscapes – could confuse the world they describe for the present day, even if they seem to capture something pervasive about the nature of spatial cognition itself, beyond the actual spaces they describe.

Not surprisingly, perhaps, Eno’s output from the 90s onwards tended to converge music and space, with most of his “albums” actually functioning more as soundtracks to installations, or as parts of installations. During this time there was collaborative and production work – some of his most renowned production work – but his practice as a solo musician seemed to be moving further and further in the direction of sound sculpture, which was, after all, a natural conclusion to the Ambient series. Even “studio” albums from this era had a conceptual art flavour, such as January 07004: Bell Studies for the Clock of the Long Now, reframing the studio in terms of visual art coordinates rather than musical coordinates.

Apart from the legendary lost album of My Squelchy Life, only one genuine studio release survives from this era – 2005’s Another Day on Earth. In some ways, I think of this as the last gasp of the impulse behind albums like Another Green World (as the title would suggest), Here Come the Warm Jets and Before and After Science. In other words, it was Eno’s last real effort to create a sustained solo art pop album. While it may have received savage reviews from some critics, I tend to think that it is underrated – like so many albums that are released out of time – and contains some of his most memorable pop tracks.

The major turning point in this trajectory was 2010’s Small Craft on a Milk Sea, Eno’s first album with Warp records. Signing with Warp was a paradoxical move for Eno, since while the label are renowned for quality control and innovative experimentation, their mantra of electronic music for headphone listening is itself extremely Enoesque. In other words, Eno was signing with a label whose very existence owed a direct debt to his experimentations, begging the question of whether they would rediscover a classicist Eno or try to draw out a more unfamiliar Eno for fear of seeming too slavishly nostalgia, or too indebted to him in the evolution of their own brand.

The answer was – a little bit of both. In some ways, Small Craft on a Milk Sea plays as two separate albums, one of which is driven by pearls of ambience with appropriately evocative, album-oriented titles, and the other of which is driven by sharp bursts of abrasive noise. In its own way, that’s a classicist statement, insofar as it dovetails Eno’s earliest tape loop and noise experimentation with his later ambient experimentation, but it was also clear that Warp were trying to shock Eno acolytes with a completely new level of intensity of angular, abrasive noise, especially by setting it alongside more recognisably ambient textures.

Since then, most of Eno’s releases for Warp have had this same fractious quality, as if anxious about settling into anything resembling a unified album-length statement for fear that it might devolve into nostalgic classicism. As a result, his discography has been nothing if not unpredictable, featuring collaborations with spoken word poet Rick Holland and Underground member Karl Hyde, and drawing upon a vast array of musical influences without ever quite settling into or fully demonstrating his mastery over any of them. The result is a sense of restlessness, which of course had always been a part of Eno’s style, but is accentuated here by the fear of falling into a late career groove that’s too easy and familiar.

Only one truly ambient album was released amidst this experimentation – 2012’s Lux, which consisted of two roughly twenty minute pieces. This was released to great acclaim, but I found it strangely unconvincing compared to some of his previous ambient albums. In part that was because the tones and textures just seemed a little too upbeat, a little too bright, compared to some of his earlier efforts. But it was also because it seemed like an ambient album made for a label for whom ambience hadn’t previously been enough, with the result that the two ambient sides felt as if they were there to cushion a more abrasive or angular core that hadn’t actually been included.

On the face of it, 2017’s Reflection might seem to fall into the same category. Like Lux, it’s an ambient album, with the different that it only consists of one track, called – not surprisingly – “Reflection.” Yet this is a very different kind of album from Lux and a very different kind of album from anything else Eno has produced in the last decade. In its own inimitable way, it is both more familiar and strange than anything else he has produced with Warp – and its strangeness has a way of taking you by surprise in the gradual, ambient fashion that Eno does so well. After all, the Ambient series was nothing if not way of experimenting with building an emergent mood – a mood that was still emergent after multiple listenings – something that Lux didn’t quite seem to grasp.

So what is it that makes Reflection so different? Well, for one thing, the tones and textures are much more sombre, moody and melancholy than most of Eno’s recent output, which has tended to be abrasively manic or polished in its beauty, but not murky in the same way as what we hear here. At the same time, it has to be said that the soundscape heavily recalls the moody apex of Eno’s ambient phase, particularly On Land and Apollo: Atmospheres and Soundscapes, both of which seemed to imbue spatial cognition itself with a kind of melancholy musicality. Finally, Reflection is starkly ambient in the manner of his best releases, never quite reaching a climax or conclusion before it gradually fades away.

Above and beyond all that, however, there’s another factor that might explain why Reflection feels so fresh. Unlike Eno’s other ambient albums, the track here actually exceeds the album, since the main form in which Reflection is designed to be experienced is as a genuinely generative piece of music – available as an app – that evolves and develops according to the time of day. When I said that the album only contains one track, then, that doesn’t actually mean – as it once did – that the album was the track. Instead, it means that the album has become a kind of portal to the track, rather than an embodiment and containment of it.

In many ways, that sense of generativity was what always made Eno’s ambient releases so evocative. Whether you’re listening to the first side of Music for Airports or the first track of On Land, there’s a strong sense that this piece of music could go on indefinitely if you just had time and space to allow that to occur. As a result, Eno’s ambient albums are poised between the finite, analog sense of space occupied and embodied by the track, and a more infinite, digital sense of space inherent in the endlessly generative potential embodied in the track itself. By actually being able to make the track endlessly generate itself, however, Eno reverses that formula.

In other words, whereas Eno’s ambient pieces once felt like analog harbingers of the digital, Reflection feels like a muted, melancholy meditation back upon those harbingers from within a thoroughly digital infrastructure. Not quite an adaptation or continuation so much as an elegant culmination of his ambient period, it’s no wonder, then, that Eno considers this to be his most sophisticated and cumulative ambient gesture. On the one hand, it’s an autobiographical reflection, a look back upon all his ambient innovations, many of which are quoted here in distant and oblique ways. At the same time, however, the piece continually – and literally – reflects back upon itself and its means of production, erasing a little bit of Eno’s agency each time it does so.

That contrast between Eno’s reflections and those of the piece itself make listening to the album version a tantalising experience, since the presence of the app doesn’t invalidate the album but instead turns it into a mere “capture” or “grab” of ambient texture rather than a self-contained “piece.” Not surprisingly, then, the progression of the album version seems to insinuate itself into whatever routines or rhythms you are experiencing when you are listening to it, to the point where it seems to have implanted its own rhythms and routines on your day long after you have listened to it as well. By the same token, it’s an album that sounds different each time you listen to it as well, as if its generative potential were tangible enough to seep through even on this short, finite excerpt.

For all those reasons, then, I personally feel that Reflection is the pinnacle of Eno’s work at Warp so far. As much as the label tried to estrange him from his previous style, he’s finally found a way to inhabit and transform that style from the inside out so as to make Reflection both one of the most personal and one of the least personal works in his very long career. Like the blurry image of Eno on the cover, you feel him drifting in and out of focus, only to fade away gradually at the end, in what feels like a perfect swansong for his ambient career as we know it and the beginning of an exciting late period in his musical development.