About

As a teenager, I became fascinated by sound – how a bass line can fill an entire room, how frequencies interact. Playing bass guitar in various bands (funk, punk, big band, glam-rock) and later working with electronic music and synthesizers, that fascination became a serious interest. In 2005, I started Giel Passier Audio Engineering.

Background & Experience

Applied Physics (Fontys Hogescholen)
Sound Projects - Graduated on and subsequently worked freelance on sub and mid-bass system design for line arrays. Focus on output optimization: port-loaded and horn-loaded designs for compact boxes suitable for rigging alongside line arrays
Brüel & Kjær (from 2006) – Specialist in sound and vibration measurement. Product demonstrations, training, and PULSE analysis software development (from support to feature development)
ASML (since 2012) – Progressed to systems engineer. Translating complex technical challenges into practical solutions

When I joined Brüel & Kjær in 2006, I officially put the business on hold. However, I continued working with sound as a hobby in my own spaces and for others. I set up my current listening room in its present form about three years ago, and since then people have regularly visited for mix checks. In early 2026, I made the decision to work 80% at ASML and fully reactivate my business.

My Approach

Grounded in theory: AES journals, "Recording Studio Design" (Newell), "Sound Reproduction" (Toole), "Acoustic Absorbers and Diffusers" (Cox & D'Antonio)
Practically focused: solving problems, improving results, without expensive marketing or quick fixes
Broad perspective: from speaker R&D and software development to measurement systems and studio optimization
Data-driven: informed decisions based on measurements and experience

Why this works

I understand loudspeaker design, signal processing, electronics and acoustics – and especially how these interconnect. My broad musical taste (hip-hop to metal, electronic music to jazz) helps me understand what different genres require from a listening environment.

Specializations

Speaker selection, placement, and integration
Subwoofer selection and integration with mains
Acoustic measurements and analysis
Room correction and DSP calibration
Passive and active acoustic treatment