Sympathetic Synthesizer System Mk1

A synthesizer created using the Web Audio API, now with AI-powered sound design.

Features

• 3 oscillators with selectable waveforms (triangle, sawtooth, square)
• ADSR envelope for volume
• ADSR envelope for filter
• Low-pass filter with cutoff and resonance controls
• Noise generator
• MIDI input support
• Virtual keyboard (qwerty-hancock)
• AI Sound Designer - Describe the sound you want in plain English and the AI will adjust the synth settings

Getting Started

Prerequisites

• Node.js 18+
• npm
• Anthropic API key (for AI features)

Setup

1. Install dependencies:

npm install

2. Create a .env.local file with your Anthropic API key:

cp .env.example .env.local
# Edit .env.local and add your ANTHROPIC_API_KEY

3. Start the development server:

npm run dev

The synth will open at http://localhost:3000

Using the AI Sound Designer

The AI Sound Designer panel lets you describe sounds in natural language. Try prompts like:

• "Create a warm pad with slow attack"
• "Make a punchy bass sound"
• "I want a bright, aggressive lead"
• "Give me an ambient texture with some noise"
• "Classic 80s synth brass sound"

The AI will analyze your description and adjust the oscillators, filters, and envelopes to create the sound you described.

Development

Build for Production

npm run build

Start Production Server

npm start

Linting

npm run lint

Project Structure

src/
├── app/
│   ├── api/chat/route.ts   # AI chat API endpoint
│   ├── globals.css         # Global styles
│   ├── layout.tsx          # Root layout
│   └── page.tsx            # Main page
├── components/
│   ├── chat-panel.tsx      # AI chat interface
│   └── synth-panel.tsx     # Synth controls and keyboard
├── lib/audio/
│   ├── audio-engine.ts     # Web Audio API wrapper
│   ├── envelope.ts         # ADSR envelope generator
│   ├── synth.ts            # Main synthesizer class
│   └── index.ts            # Audio module exports
└── types/
    └── qwerty-hancock.d.ts # Type definitions

Tech Stack

• Next.js 15 - React framework with App Router
• TypeScript - Type safety
• Vercel AI SDK - AI integration with streaming
• Anthropic Claude - AI model for sound design
• Web Audio API - Audio synthesis
• qwerty-hancock - Virtual keyboard

License

MIT