We started Geelen Audio because we wanted to change how people approach sound engineering. The audio world often feels hidden behind a curtain of mystic claims and subjective hype, but we believe it should be open, transparent, and driven by clear engineering logic.

Our goal is simple: demystifying how audio hardware actually works, share our blueprints openly, and build a community where we can all develop great audio gear together.

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Our Philosophy

  • Objective Measurement: We don't rely on guesswork. Every project we share is backed by actual performance data and testing parameters. If it can’t be measured and verified, we don't use it.
  • Predictability and Logic: We design our projects logically from the ground up, focusing on component availability, manufacturing predictability, and clear, repeatable assembly.
  • Open-Source Collaboration: Everything we do is open-source. We share our full blueprints and documentation so you can audit the designs, replicate them at your own workbench, and improve them with us.

Who we are

We are Pieter and Celine—partners in life and the creators of this project. Geelen Audio is the result of our combined perspectives: Pieter’s obsession with the physics of sound and Celine’s belief that good ideas are meant to be shared

Pieter | Researcher & Maker

I’ve been a "science guy" and a maker for as long as I can remember. Growing up, my home was filled with serious high-end audio gear—massive tube amplifiers, exotic premium cabling, and pristine speakers. It taught me what great sound feels like, but as I got older, I started questioning the lack of objective proof behind a lot of it.

The turning point for me was simple: I noticed my standard pair of Beyerdynamic headphones easily outperformed complex speaker setups that cost a small fortune. To me, that was proof that exceptional sound isn't magic—it’s just a solvable engineering problem. I started building, testing, and measuring my own hardware to find the objective truth behind great audio, focusing entirely on data, predictability, and physics.

Celine | Community Builder

While Pieter was happy quietly working away in his private workshop, I saw how much value was tucked away in his notebooks and test data. I motivated him to take his research out of the garage and put it online where other people could actually use it and build upon it.

My role at Geelen Audio is to focus on the community. I help translate complex engineering data and technical documentation into open, approachable projects. I want to make sure that anyone who wants to learn has a welcoming space to share their measurements, talk through their builds, and collaborate.