The Hovalin: A real-time synesthesia translator

Written and submitted by Kaitlyn Hova

This guest blog post is by Kaitlyn Hova. Kaitlyn is a professional violinist, composer, full stack web developer, designer, neuroscientist, and core team member of Women Who Code. She is also a synesthete—which means her sensory perception is quite different from what most people experience. Kaitlyn spoke on the TEDMED stage in 2016, and you can watch her talk here.


Most people don’t expect their understanding of the senses to drastically change beyond what we learn in grade school: sight, smell, touch, taste, and hearing. I was 21 years old when I made the jarring discovery that none of my fellow students experienced vivid colors and shapes when they heard musical notes. At first, my classmates called this ability “weird”. Actually, I later learned the official term: “synesthesia”! Finding out that you physically experience the world in such a fundamentally different way can feel isolating. However, it turns out that 1 out of 23 people have some type of synesthesia. What if the study of this ability that was once thought to be “strange” is actually the study of the diversity of the average human sensory experience?

Matt and Kaitlyn Hova, co-founders of Hova Labs

I had always wanted to find a way to accurately convey my experience of seeing sound. I believed that if people could see a simulation of my synesthesia in real time they would be able to make the jump to understanding the nature of it. With this idea in mind, my husband Matt and I co-founded Hova Labs three years ago. One of our first projects was creating a real-time sound → color synesthesia translator violin. Imagine a guitar tuner, but instead of the tuner showing the note “C” it shows what I see when I hear the note “C”, which is the color red. Further, imagine that the brightness of the color is driven by the volume of the instrument being played. (I should be clear, the colors that I experience when I hear notes of music are an experience that is unique to me. If we both hear the note “C” and you see blue but I see red, neither of us is “wrong”, we simply have different associations in our brain.)

Creating a synesthesia-translating violin wasn’t easy—it took us a year and a half of prototyping. We could have easily just strapped LEDs on any violin but we had a VISION: a synesthesia translator glowing violin. First, in order to figure out how to drive the lights inside of our violin, I created a color-coded map of a piano. Additionally, we knew we wanted the violin holding the synesthesia-driven lights inside of it to be translucent, yet at the time (2014), such an instrument didn’t exist (or if it did, it was probably way too expensive). Determined to make our vision a reality, we decided to take our concept a step further. We created The Hovalin: our 3D printable acoustic violin.

Piano keys through the eyes and ears of synesthete Kaitlyn Hova

In October of 2015, we released the Hovalin, and we made it available for anyone to download online along with a short shopping list of materials and “how-to” build instructions. Since the launch, we’ve continued to improve the design. You can see me playing our v3.1 design in my TEDMED talk!

After launching the Hovalin, we soon realized that our project had the potential to be a lot larger than we originally thought. Though today’s music education programs are systematically underfunded, STEM (science, technology, engineering, and mathematics) grants are introducing 3D printers to kids at these same schools. We saw this as an opportunity: why not 3D print your music program?

Creating instruments with 3D printers is a solution that has never existed before. Today, all of the files are available to download for free at hovalin.com. If you have access to a consumer-level 3D printer, the total cost (including plastic, tuning pegs, strings, and bow) is $65. And this is just for one violin. With bulk purchases, we believe that this cost could be reduced drastically.

We already have a pilot program in Oakland, California, and we hope to expand to more schools around the country and the world. We believe that STEM programs can empower kids to solve their problems creatively while supporting the often under-funded music education programs in schools. We attribute our diverse backgrounds in music and tech to creating the Hovalin, and who knows what other great projects will come from kids that are given the chance to think creatively with STEM programs.

If you’re interested in learning more about Synesthesia, I encourage you to check out The Synesthesia Network. Also, you can check out more nerdy violin electronics in this blog post at Hova Labs.