Background - grellaudio consulting - everything about headphones and acoustics

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Everything about headphones and acoustics
Everything about headphones and acoustics
Everything about headphones and acoustics
Everything about headphones and acoustics
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Axel grell
I am an auditory guy!


Axel Grell,  grellaudio consulting
At the age of 12, Axel built his first speaker box and couldn't stop since then. He later studied communications engineering and completed his diploma thesis on an active speaker system in 1991. In addition, Axel mixed bands with his self-built PA system.
In 1991, Axel started as a headphone developer at Sennheiser electronic and worked there for 27 years in various management roles. Since 2019, he has been working as an independent consultant for headphones, accompanying various development projects and providing specific advice.
Research and Progress


Without fundamental research, the scope for technical innovation is limited: grellaudio consulting works closely with the Institute of Communication Technology (IKT) at Leibniz University Hannover.
Dr. Jürgen Peissig und Axel Grell
To improve the sound of headphones, a deep understanding of the interaction between the reproducing headphone, the listener's hearing, and perception is needed. This interaction is currently being researched. In collaboration with Prof. Dr. Jürgen Peissig from the IKT, this connection is being investigated.
The project involves developing new measurement techniques that allow for better alignment between measurements and perceived sound. The research findings are incorporated into the development work of grellaudio consulting, resulting in faster, more comprehensible assessments of sound.
Press reviews
In Interview!


The interview was conducted by Karoline Grell with Axel Grell in April 2021.
How do people know you?
Through the media and trade press, through interviews and product presentations, and online forums. You can find me at trade shows such as IFA, High End Munich, CanJams, Tokyo Headphone Festivals, and CES.

Thinking of lifestyle and design, what role do these topics play for you?
First and foremost, design must support function. Since headphones are a product that is close to the body, wearing comfort and ergonomics play a crucial role. What the customer wants is crucial, both in terms of design and, to a large extent, sound. People have different sound preferences.

You are well-known in the headphone industry. Why?
Simply because I have created headphones that have set standards for decades, such as the HD 600 and HD 650 from Sennheiser. And with the HD 800, which I developed and brought to the market for Sennheiser and also appeared as the face of the advertising campaign, I opened up a new standard and a new market segment. Namely, headphones above 1000 Euros. I am also known for expressing my views on the topic of "How to make headphones?"
Who knows you?
People interested in headphones and HiFi, particularly in the audiophile field. But I also work in the entry-level segment.

How do you give headphones their distinctive sound?
I sit in the lab and basically create some kind of being. I have an idea of how I want the headphones to sound, a first idea, so to speak. I can only hear that and not measure it. That is crucial.

How does it work?
It's like an acoustic idea that already exists in my head. I build a prototype and listen to the music of my target audience with it. Using measurement technology, I optimize the sound to match my expectations.

What drives you?
The goal is always to create the best-sounding and functioning product in the respective price range – for the money available. It's not just about the sound; it's also about making it work as I envision it, in a comprehensible way.

Axel Grell and Karoline Grell
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