About

Background

DEM Audio is run by me, Arnaud Demion, in Valais, Switzerland. I'm an engineer, and I trained as a physicist. I did a master's in mathematical and theoretical physics, then a PhD in condensed matter physics at Aix-Marseille University, working on electronic transport in graphene and topological insulators.

That's a long way from loudspeakers, but the tools carry over well. Wave propagation, dynamical systems, signal processing and numerical simulation are what I use every day in audio too. I treat a loudspeaker as a physics, measurement and filtering problem, and fashion or folklore don't come into it.

A loudspeaker can be modelled, measured and corrected, so I don't claim anything I can't back with a measurement or a physical model. When others do, I say so on the blog.

Why I wrote LinFIR

I needed a tool that would show me what a real DSP does to a real signal, with equalisation, causality and latency as they really behave, rather than an idealised curve that looks good on a graph. Nothing did that the way I wanted, so I wrote it. Other designers use LinFIR today, and so does Amadeus.

What I work on

Today that means three things. I develop and sell LinFIR. I take on engineering and consulting work for manufacturers who need acoustic or DSP expertise. And I design custom loudspeakers for people who want a system built for their room.