How did your musical life begin?

I started off really early, at my own request at age three learning classical piano. I was around 11 when my piano teacher introduced me to the contemporary classical genre with works by Andriessen. Given my current practice it's remarkable, possibly crucial, that my teacher was attracted to contemporary arts in general and introduced me to it, as I grew up in a small and rather traditional village in Limburg, in the south Netherlands.

When did you decide to be a composer?

I didn't go to conservatoire. I knew that I wanted to keep my musical intuition solid and that studying music at university would confuse me. I figured as a 17-year-old that if I studied composing in colour, fabric, wood, ceramics, words, architecture, I would learn how to compose, only in different materials. That's how I got to studying design. This was in the 90s, pre-digital revolution, which meant manually fabricating physical artefacts in workshops, using many techniques and materials.

Having no access to a piano, I bought an electric guitar with distortion pedal. Very soon the guitar was left in a corner and my focus was the distortion pedal, introducing me to a world of electronic music devices. It seemed completely normal at the time but it was really a combination of factors. I studied in Eindhoven, home of Philips, and would find a plethora of obsolete audio electronics such as reel tape recorders, organs, synths and obscure unidentified sound processing machines in skips or junk shops. Former Philips employees would retire and have a clear-out; I happened to be at the end of the life cycle of these objects. My music writing became exclusively electronic and I acquired technical sound engineering and music production skills. I call it writing, because I was writing pop songs, although the structure my songs only occasionally followed the logic of pop.

When did you begin to make the sort of work for which you have become known?

In 2007 I was commissioned to compose a work for the exceptionally long reverberation of a gasometer in Oberhausen in Germany, Shakespeare and Hedgeshear. This was the moment when my electronic and classical backgrounds fused into an acousmatic piece for concrete music, sound processing, recordings, strings and synth. It was also the moment when visual aspects entered my practice, from my background in design, and when my fascination for organically randomised micro-textures emerged.

Did moving to the UK have an influence on your work?

I found that in in my new habitat in the sticks in Pembrokeshire I was surrounded by these rustling micro-textures in nature! After years of living in redundant office blocks, full of AC white noise, short-slap reflections from empty floors, high-voltage humming and screeching elevators, I immersed myself in my new soundscape. Endless walking and hours of field recordings, taking in everything I could hear or see. I was on the Strumble Head peninsula, which has very high cliffs echoing sounds from seal and bird calls from many angles. After a while I was able to zoom into the rustling of bracken on the coastal path and the sound wind produces as it hits various surfaces. Or the awareness of melodies in a landscape, certain calls of birds, yet always unpredictable. It was a complete revelation which turned my music writing into composing. My tempo changed, my philosophy changed. It's my source for the artistic knowledge I need for my compositions.

What's the role of the performer in your work?

Analysing natural soundscapes resulted in experimenting with how to use their very special sense of time, the predictability in their unpredictability. Whenever I tried a similar timing on piano or with synthesised sounds it was too precise. I was too focused on getting it right. The sound of wind is a result of parameters, not of wind wanting to create that sound.

I developed a series of works where a sound is secondary to the action that generates it. These works typically feature non-musicians. I had already done this in the gasometer piece, using two table tennis teams to create a transparent stochastic sonic texture. I continued with Étude for kung-fu, gymnastics, basketball, viola, piano and soprano. The gymnasts perform a set of jumps on a horse and crash-mat, generating a rhythm, but each gymnast has a slightly different cadence because they have to judge when it would be safe to execute their sequence after the previous gymnast finishes theirs.

In 2012, to a commission from the MATA festival in New York, I composed another work featuring non-musicians, Killing Time. I wanted to bring the rich natural soundscape of Pembrokeshire to urban New York so I programmed field recordings of individual sounds into software instruments. The software instruments were triggered by a metal on metal contact, closing the electronic circuit, and I used knitting to recreate a natural timing. The timing of metal needles touching one another is a secondary result of the act of knitting a pattern. At the end of a row, or when yarn is gathered, the needles don't touch at all, causing predictable yet still unpredictable rests. Each knitting performer ‘plays’ one field recording software instrument per movement: for example, a dense texture of dissected particle sounds, like wind of the rustling of leaves, or a melodic segment which is triggered only ever so often, like when you know that birds are in a landscape but don't know when you will hear them.

Where is your work going next?

All these works were studies in gaining more understanding of what I want to achieve in composing. They increasingly brought me into digital realms, sitting in front of a laptop, so in the last few years I have developed analogue materials to bring back a sense of physicality in creating works. I'm working on a series rethinking sheet music, converting my findings in effects processing, engineering and composing into something an ensemble from the 1700s would be able to perform.

In the first, Turner Piece, the rustling sound of turning a page of conventional sheet music becomes a musical instrument in its own right. Each musician has a page-turning-part within their scored part, so they are performing two instruments at the same time. The paper instrument's timbre is determined by paper quality, varying from high-pitched, microtonal rice paper to lower-pitched heavy brown stock. A visual element is added by choreographing the page-turning throughout the ensemble.

In my latest pieces, IMAGIRO Largo and IMAGIRO Landmannalaugar, I'm liberating sheet music from its book form into long panoramic scores, so the musicians have to move to read their parts. This opens up a vast complexity of opportunities. I can achieve panning and phasing by literally moving multiple sound sources through a spectrum. Or fading instruments in and out of earshot even though they might play at a loud volume. I can express the sensation of walking through majestic natural landscapes through scale, textures and tempo.

Because the panoramic scores are compositions describing the music a landscape evokes in me, it felt wrong to use conventional notation. I developed a technique in which dynamics, textures, rests, pitch cues and pitch changes are condensed into a single graphic line, like a skyline. Now I could become even simpler in my choice of materials with just ink and brush on paper, letting my intuition channel the music I have in mind through my body into a stroke of black ink.

Underneath the graphic line is a section where each instrument has a score with step sizes on grid lines. Musicians follow their steps at the indicated tempo. With six players progressing through the score at varied speeds, harmonies fold open from this single ink and brush line, like a piece of origami emerging from a single sheet of paper. Like a walk through nature, the panoramic score can also be read both forward and in reverse.

Everything I've been working on up to now can be represented in these panoramic scores. Yet it gains in elegance with simplicity. With the first piece, Largo, I got carried away. I was working to a commission, limiting my concept to concert space dimensions, rather than wrapping it through multiple spaces of a building, as I initially envisioned. I used charts to work out how each musician could make a maximum of 110 steps at a minimum of 30cms per step, covering the 10 × 14 × 10 metres of wall space of the concert venue minus rounded angles: a brain-teaser! The panoramic score is U-shaped, with two players starting in the middle, walking outwards to each side, performing the same melody yet mirroring one another's movements. Then they reverse their paths, picking up more players. It seems very mathematical, very dry, but the finished piece still sounds emotional.

Largo turned out to be too complex to realise within the budget and time available. I wanted it to be performed, so I made a version in conventional notation. This work now exists as a graphic panoramic score and as conventional sheet music, both resulting in the same music when performed. But I also wanted to introduce my new panoramic scoring technique at the premiere so I made a second work, Landmannalaugar, which uses interpretation of the sweeping lines between the pitched cues, which doesn't happen in Largo. Largo is more like a perfectly manicured park, Landmannalaugar a roam in the wilderness.

A panoramic score such as IMAGIRO Largo requires quite specific additional techniques for the performers: they need to walk, to make the cognitive adaptation to read a graphic score, and they're performing a choreography in which their paces which determines the pitch. It's an immersive way of working with a location and the audience are able to follow the music visually. The premiere of Landmannalaugar showed me how effective it can work. I'm considering starting a dedicated ensemble for it.