How to use:
- Click "Start Tuner" and allow microphone access
- Play individual strings or strum multiple strings
- Watch the tuning meters for each string
- Green = in tune, Yellow = close, Red = needs tuning
Features:
- Real-time polyphonic detection (6 strings simultaneously)
- Harmonic pattern recognition (detects missing fundamentals)
- Sub-Hz accuracy with parabolic interpolation
- Multiple tuning presets (Standard, Drop D, DADGAD, Half Step Down)
- Full-range spectrum analyzer (60 Hz - 20 kHz)
- Logarithmic waveform display with auto-gain
Architecture:
- 100% client-side processing - all audio processed in your browser
- Privacy first - no audio data sent to server
- Near-native performance - C++ DSP core compiled to WebAssembly
- Zero network latency - ~10-20ms audio processing latency only
- Offline capable - works after initial load (PWA with Service Worker)
- Installable - add to home screen on mobile devices
Technology Stack:
- DSP Core: C++17, KissFFT, CQT analysis, harmonic detection
- Frontend: WebAssembly (73KB), Web Audio API, Vite
- Server: Static file serving only (no audio processing)
Privacy Policy
EriChord respects your privacy. This application processes all audio data locally on your device using WebAssembly.
We do not collect, store, or transmit any audio data, personal information, or usage analytics to external servers.
The microphone is only accessed when you explicitly start the tuner, and audio processing occurs entirely within your browser.
Data Processing: All audio analysis is performed in real-time within your browser. No audio recordings are stored on your device or transmitted over the network.
Permissions: Microphone access is required for tuning functionality and is only used when you actively enable the tuner.
Third Parties: This application does not integrate with or share data with any third-party services or advertising networks.
Cookie Policy
EriChord uses minimal local storage mechanisms to enhance your experience. We do not use tracking cookies or advertising cookies.
Service Worker Cache: We use browser caching (via Service Worker) to enable offline functionality and improve performance.
This stores static application files locally on your device for faster loading and offline access.
Local Storage: Application settings and preferences (such as selected tuning configurations) may be stored locally in your browser's localStorage.
This data never leaves your device and can be cleared at any time using the "Reset App" button or your browser's settings.
No Tracking: We do not use cookies for tracking, analytics, or advertising purposes.
How to Clear Data: You can clear all cached data and reset the application at any time by clicking the "Reset App" button in the footer,
or by clearing your browser's cache and site data.
Copyright © 2026 Hochwald LLC. All rights reserved.
