Klesis

Send text through sound.

A progressive web app that encodes text into audible sound waves and decodes them on nearby devices — no internet, no pairing, no Bluetooth. Just sound through air.

🔊 Try it live

Features

• Acoustic messaging — encode and decode text via sound using ggwave
• 6 protocol modes — 3 audible speeds + 3 ultrasound speeds
• Real-time visualizer — frequency spectrum bars on desktop, fill bar on mobile
• Works offline — full PWA with service worker caching
• Installable — add to home screen on iOS and Android
• 140-byte messages — compact UTF-8 payloads
• Echo prevention — mic mutes during playback to avoid self-reception

Quick Start

npm install
npm run dev

Tech Stack

Vanilla JS · Vite 6 · ggwave 0.4.0 (WASM) · Web Audio API · Canvas

Platform Notes

Ultrasound protocols (modes 4–6) are broken on iOS/Safari due to Web Audio limitations. Audible protocols work fine everywhere.