"Ever since I first played solo Bach on my violin, I've been fascinated by how changing colours of differently tuned harmonic intervals shape and transform the music. In my compositions I make music using intervals found amongst the natural harmonic partials, an approach sometimes called just or rational intonation (JI). These are sounds that can be accurately played by ear, by carefully listening to how very small differences of pitch create beating, resonance, fusion, and reinforce combination tones. These subtle psychoacoustic interactions are at the heart of experiencing harmony, which is what my work is about.

As I came to work this way, I was curious if the approach I use in my own compositions could also be applied to Bach in a strict way, by composing the fine shadings of intonation according to JI intervals. Over the past 25 years, I kept coming back to this work, but it was the ongoing collaboration with Sara Cubarsi, beginning with a first meeting in Cat Lamb's studio in Berlin a decade ago, that led me to write and us to record the realisation documented on this disc.

I have added a second violin part to Bach's solo violin sonatas, music that began as sustained harmonic drones on mostly open strings and harmonics, but which gradually evolved into a kind of personal take on harmonic counterpoint, and became a gentle conversation between my own music and Bach's, finding my way by ear. It was very inspiring to collaborate with a composer who invented so many ways of exploring harmony, and to revisit the old question whether music that moves freely through many tonal regions needs a "well tempered tuning", or if it can also work in a microtonal re-interpretation using many different shadings of pitch.