Coil Earphones
The Coil Earphones project is a concept development study focused on form-giving and ergonomics through the use of rapid prototyping and 3D printing. This project builds on a previous concept study, which emphasized rapid ideation and producing concept proposals. In late 2024, I revisited this earlier work, aiming to improve and modernize it.
The updated design retains elements from the previous versions but significantly enhances ergonomics and fit. The outcome is a concept proposal that has been tested for comfort through multiple 1:1 scale model iterations and in-ear testing.
Keywords: Concept design, ideation, rapid prototyping, ergonomics, 3D printing, form-giving
Background & Initial Ideation
The earliest development of this project began in 2019 during a design concept sketching and ideation course. As part of the course, I undertook a common industrial design exercise of generating 100 sketches for a product, which in this case, was earphones or headphones. Over a few days, I produced more than 150 proposals, ranging from feasible designs to very, well, silly ones.
Defining Proposals
This wide range of sketches were then narrowed down to two main form-concepts. Then, more ideation was made on these base concepts to see if they can be further improved. After this, two of the best designs were selected for their unique forms and details, as well as their feasibility for production.
This wide range of sketches were then narrowed down to two main form-concepts. Then, more ideation was made on these base concepts to see if they can be further improved. After this, two of the best designs were selected for their unique forms and details, as well as their feasibility for production.
First Concept Visualizations
After the course ended, I revisited the concepts to further develop them.
I created 3D models of both designs using SolidWorks and rendered them into presentable visuals with KeyShot. This allowed me to visualize the concepts in more detail and refine their forms, leading to more polished proposals.
After the course ended, I revisited the concepts to further develop them.
I created 3D models of both designs using SolidWorks and rendered them into presentable visuals with KeyShot. This allowed me to visualize the concepts in more detail and refine their forms, leading to more polished proposals.
Product renderings of the two chosen and refined design directions (2020)
Coil Concept Development
The motivation to update this project came from an idea to experiment with my newly acquired Bambu Labs X1C 3D printer. This provided an opportunity to explore how 3D printing could be leveraged for rapid prototyping. My previous experience with earphone design was the perfect fit for testing ergonomics-driven development with 1:1 printed scale models.
For form-giving, I retained the best forms and design details from earlier versions of the earphones while focusing primarily on improving the design and testing ergonomics.
The motivation to update this project came from an idea to experiment with my newly acquired Bambu Labs X1C 3D printer. This provided an opportunity to explore how 3D printing could be leveraged for rapid prototyping. My previous experience with earphone design was the perfect fit for testing ergonomics-driven development with 1:1 printed scale models.
For form-giving, I retained the best forms and design details from earlier versions of the earphones while focusing primarily on improving the design and testing ergonomics.
Ergonomics-Driven Ideation
The process began with loose ideation sketches, which were quickly translated into 3D software to create the first rough models for 1:1 scale prototyping. The general dimensions were accurate from the initial test model, allowing for swift experimentation with details and shapes to test and iterate ergonomics and functionality.
3D printed 1:1 rapid prototyping models
Rapid models for prototype testing
Iterative Rapid Prototyping
Due to the scale and fast printing speeds, I was able to model and hand-test variations of the main shapes rapidly. The forms evolved naturally from this iterative prototyping process. The process began with modeling and printing one or two variations at a time, testing them personally, and then adjusting the designs accordingly.
Due to the scale and fast printing speeds, I was able to model and hand-test variations of the main shapes rapidly. The forms evolved naturally from this iterative prototyping process. The process began with modeling and printing one or two variations at a time, testing them personally, and then adjusting the designs accordingly.
Hands-On Testing and Fit Evaluation
Each prototype was tested in-ear to assess comfort, feel, and overall fit in real use. Based on how subtle shape changes affected the feel and wearability, I continued refining the forms until the ideal fit was achieved.
In-ear prototype testing
Grip Ergonomics
To ensure secure handling, I included the familiar “stick” element commonly seen in popular earphones as a starting point for the design. This form then tapers into the upper parts, creating intuitive finger placement. I favor this shape for its tactile feel and ease of use. It naturally supports a three-point grip that feels comfortable and less prone to accidental drops than many alternative designs.
To ensure secure handling, I included the familiar “stick” element commonly seen in popular earphones as a starting point for the design. This form then tapers into the upper parts, creating intuitive finger placement. I favor this shape for its tactile feel and ease of use. It naturally supports a three-point grip that feels comfortable and less prone to accidental drops than many alternative designs.
Natural feeling 3-point finger grip
Final print prototypes with silicon ear tips and main outer part scale models
Final Scale Models
After extensive rapid form exploration and prototyping, I proceeded to create a high-definition version of the concept. The final design incorporates the most ergonomic forms, while addressing initial part design. I printed the final prototype versions, and attached silicone ear tips to them for a more refined look, feel and wearability testing. Additionally, I printed prototypes of the main outer parts for real-life scale evaluation.
After extensive rapid form exploration and prototyping, I proceeded to create a high-definition version of the concept. The final design incorporates the most ergonomic forms, while addressing initial part design. I printed the final prototype versions, and attached silicone ear tips to them for a more refined look, feel and wearability testing. Additionally, I printed prototypes of the main outer parts for real-life scale evaluation.
The Concept
The final design features a light stone colorway with fine aluminum detailing. The back resembles a speaker coil, reinforcing the earphone's function as a music device while adding a jewelry-like detailing when worn. The organic forms follow the natural contours of the ear, and the circular detailing gives the design a timeless, uniform aesthetic. A physical button is included for controls, as I believe tactile button feedback offers a clearer feeling user-experience.
The visual expression of the product strikes a balance between premium quality and approachability, positioning the design between similar products from brands like Sony and Bang & Olufsen.
Project on-going. Next steps include designing and thoughtfully crafting a case concept and prototype for the earphones.