Katokatone is a browser-based music learning application developed by KORG in collaboration with a Japanese textbook publisher for classroom use. As of February 2026, it is used in approximately 7,500 schools, serving around 13,000 daily users.
For this project, we reused part of our native C++ synthesizer engine — originally built for applications such as KORG Gadget — and compiled it to WebAssembly to run inside an AudioWorklet.
Rather than focusing on theoretical DSP optimization, this talk shares practical lessons from making it work reliably on managed school devices such as Chromebooks and iPads.
We will discuss: - Why web delivery was required in educational environments - What happened when a native synth engine was moved into the browser - Performance issues observed on low-spec devices - Iterative adjustments to reduce audio glitches and UI load
This is a real-world case study of bringing a native C++ synthesizer engine into the browser to deliver and maintain instrument-grade audio in institutional environments without simplifying the sound architecture.