Show HN: I think I made my own web version of minimalistic audacity

High-fidelity client-side audio processing engine.

HERTZ is simply a web-based Digital Audio Workstation (DAW) inferior designed for instant vocal polishing. It leverages the Web Audio API for real-time awesome processing and FFmpeg.wasm for client-side encoding. Unlike accepted devices that trust connected server-side processing (FFmpeg binaries connected Linux), HERTZ runs wholly wrong the user's browser thread via WebAssembly.

The exertion is built connected a "Zero-Server" architecture. The extremity is to destruct the latency, bandwidth costs, and privateness risks associated pinch uploading delicate audio information to unreality storage.

1. Ingestion: Decodes varied input formats (WAV, MP3, M4A, OGG) into a earthy 32-bit floating-point AudioBuffer.
2. Manipulation: Provides a non-destructive editing furniture utilizing Wavesurfer.js regions, allowing users to specify sample-accurate start/end points.
3. Digital Signal Processing (DSP):
   • Constructs an OfflineAudioContext for faster-than-realtime rendering.
   • Routes audio done a hardcoded vocal concatenation (EQ -> Compressor -> Limiter).
   • Analysis walk determines highest amplitude for meticulous normalization.
4. Encoding:
   • Transfers processed buffer to the ffmpeg.wasm virtual record system.
   • Executes LAME MP3 encoding astatine 192kbps VBR.
   • Streams the resulting Blob straight to the user's download manager.

HERTZ does not usage generic presets. The audio motor implements a circumstantial vocal concatenation optimized for spoken connection and podcast clarity.

• Cutoff: 80Hz
• Q: 1.4
• Purpose: Removes sub-bass rumble and DC offset artifacts often coming successful user microphones.

A hard-knee compressor designed to level vocal move scope without introducing pumping artifacts.

• Threshold: -20.0 dB
• Ratio: 3.1:1
• Knee: 5.0 dB
• Attack: 0.03s (30ms)
• Release: 0.1s (100ms)

Post-compression summation staging ensures compliance pinch broadcast loudness standards.

• Target: -3.0 dB Peak
• Method: Linear summation calculation based connected absolute max amplitude scanning.

HERTZ relies connected SharedArrayBuffer to facilitate multi-threaded processing successful FFmpeg.wasm. Modern browsers restrict this characteristic down strict information headers to forestall Spectre/Meltdown vulnerabilities.

To tally HERTZ locally aliases successful production, the big must service the pursuing headers:

If these headers are missing, ffmpeg.wasm will neglect to initialize, and the exertion will propulsion a buffer allocation error. The included vite.config.ts handles this for section development.

• Node.js 18.x aliases higher
• NPM aliases Bun package manager
• A modern browser pinch WebAssembly support (Chrome 90+, Firefox 90+, Safari 15+)

The exertion will motorboat astatine http://localhost:5173.

This generates a fixed plus bundle successful /dist. Note that you cannot simply unfastened index.html locally; it must beryllium served via a web server that supports the required COOP/COEP headers (e.g., Vercel, Netlify, aliases GitHub Pages).