Bärtsch came up through classical training in Zurich and studied philosophy alongside music, which tells you something about how his brain works. He's not interested in improvisation as a kind of free expression or personality display. For him, the structure is the point. His compositions — he calls them 'Modul' pieces, numbered rather than titled — are built from interlocking rhythmic cells that the band repeats, layers, and gradually transforms. It's closer to Steve Reich or Conlon Nancarrow than it is to Bill Evans, even if the piano voicings occasionally nod toward jazz harmony.

Ronin, his long-running working band, became a genuine collective over years of playing together. The lineup has included Sha on bass clarinet and contrabass clarinet, and the group's sound is heavily defined by that low-end woodwind color against Bärtsch's clipped, percussive piano style. He doesn't play piano the way most jazz pianists do — there's very little warmth or sustain in the attack. It sounds almost like a mallet instrument sometimes, dry and exact. That's a deliberate choice, and it's central to how the music functions.

The ECM connection matters here. Manfred Eicher signed Bärtsch and Ronin, and the label's recording aesthetic — that famous space and clarity — suits the music perfectly. Albums like Stoa (2006) and Llyria (2010) sound like they were recorded inside a very clean room, which is not a complaint. The production doesn't add atmosphere; it just lets the precision of what the band is doing sit right in front of you. You can hear every decision.

Bärtsch also runs a Monday night residency at his Zurich club Exil that went on for years, which shaped Ronin's music in a specific way. Playing the same space every week, for the same crowd, creates a different kind of pressure than touring does. You can't rely on novelty. The music has to work on repetition, which is exactly what his compositional approach demands anyway. That feedback loop between the residency and the writing is probably why Ronin sounds so locked-in — they genuinely played these pieces hundreds of times before they recorded them.

He's also released solo piano records, including Hèrse (2008), which strips away the groove element almost entirely and gets closer to the minimalist composition side of what he does. Those records are worth knowing, but they're a harder entry point. If you're new to Bärtsch, start with Ronin's live recordings or Llyria — you need the rhythm section to understand what makes this music tick. Once you've got that in your ears, the solo work makes a lot more sense.