Dallas harmonica player Christof Hettiger invents The Bullet Chamber

A musician standing holding a harmonica

Christof Hettiger with his invention, The Bullet Chamber. Photo: Jessica Waffles

In the world of harmonica playing, innovation isn’t always about creating new sounds but rather making it easier for everyone to access the music. Christof Hettiger, a talented Dallas harmonica player living with arthrogryposis multiplex congenita (AMC), has developed a groundbreaking invention called The Bullet Chamber that promises to do just that.

This harmonica adapter is not only a game-changer for those with hand disabilities like Hettiger’s, but also for beginners and people with small hands who may struggle to cup the harmonica while playing.

Harmonica adapters

Parts of Christof Hettiger’s harmonica adapter invention The Bullet Chamber. Photo: Jessica Waffles

The Bullet Chamber, aptly named for its integration of a bullet microphone into its design, is the brainchild of Hettiger’s ingenuity and perseverance.

The first iteration of the adapter came when Hettiger began experimenting with a resin printer in January 2022, and the design has progressed into the sleek execution of the current 3D-printed model.

“I showed the second prototype at a harmonica convention,” Hettiger said. “People liked the concept, but they gave me critical advice. First, they were concerned about the distance between the bullet mic and the harmonica. Usually the distance is about half an inch. The prototype was about 1.5 inch. The sound quality was fine but it was susceptible to feedback. The second concern was the air leakage around the harmonica.”

A 3d-printed harmonica adapter

The Bullet Chamber easily embeds a harmonica microphone. Photo: Jessica Waffles

A musican sitting at a desk with a 3D printer and computer

Christof Hettiger at his home workstation where he designs and 3D prints The Bullet Chamber. Photo: Jessica Waffles

“I’ve been developing [the current design] over the last 6 months,” Hettiger said. “Now with the mouthpiece I have, I learned how to attach the silicone to the plastic. Now I can get the perfect gasket seal.”

One of the most exciting aspects of Hettiger’s invention is its potential to expand beyond accommodating hand disabilities. He envisions a future model that caters to guitar players.

“I want to make a model that can help a musician cup a harmonica while playing guitar,” Hettiger explained. “I believe I could easily put it on a rack, then somebody would be able to take advantage of that seal on something that’s completely hands-free.”

Two side by side photos holding a harmonica with and without an adapter

The Bullet Chamber gives the musician an ergonomic hand position for cupping a harmonica. Photo: Jessica Waffles

The Bullet Chamber isn’t just about innovation; it’s about inclusivity. Hettiger emphasizes that his invention is for anyone who experiences discomfort or difficulty in cupping a harmonica to a bullet mic.

“Everyone’s hand disability is different,” he noted. “The other use case would be someone who has small hands, or even beginners [to harmonica]. Cupping a harmonica is not intuitive. It’s for anyone who has trouble cupping a harmonica to a bullet mic. It cups it for you. It’s like training wheels.”

With his invention, he not only enhances accessibility to harmonica playing but also fosters a more inclusive musical community.

A musician standing holding a harmonica

Christof Hettiger. Photo: Jessica Waffles

Two 3d printed harmonica adapters

Two versions of The Bullet Chamber, the one on the right is larger. Photo: Jessica Waffles

In the video below, watch Hettiger demonstrate the cupping abilities of The Bullet Chamber with local artist Jade Nickol – a musician he collaborates with often.

Hettiger is a freelance musician (when he’s not putting his master’s degree in engineering to use at work) and is always looking for more locals to play music with. He can be reached through his Instagram page for anyone interested in collaborating.

A 3D printer

The Bambu Lab 3D printer is a high-level printer that is also user-friendly. Photo: Jessica Waffles

Anyone interested in seeing Jade Nickol and Christof Hettiger perform together at Deep Ellum Brewing April 6 at 3:30PM – 6:30PM and the Ennis Bluebonnet Trails Festival April 20 at 12:00PM – 1:30 PM.

You can also catch Jade Nickol at Lava Cantina on March 30 at 8:00PM.


Jessica Waffles is a freelance photographer/videographer and regular contributor to KXT. 
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