Resound — Ultra-Low Latency LAN Audio

Resound is a premium, high-fidelity audio streaming system built with Rust (Tauri) and TypeScript (Next.js). It captures system audio on a Host and streams it with sample-aligned synchronization to multiple Receivers over a local network.

🚀 Key Features

• Sample-Aligned Sync: Perfect audio alignment across multiple devices using a fixed 150ms playout delay.
• Dual-Mode Capture (macOS):
  • Perfect Sync: High-fidelity loopback via the Resound Audio aggregate driver (powered by BlackHole).
  • Lightweight Sync (Driverless): Zero-configuration capture using ScreenCaptureKit.
• mDNS Auto-Discovery: Receivers instantly find hosts on the LAN without IP configuration.
• Premium Web Client: A mobile-responsive Next.js interface for quick, driverless receiving.
• Live Status Feedback: Real-time connection monitoring and "On Air" feedback.
• Advanced Controls: Per-client gain boost (1x to 3x) and multi-channel hardware monitoring.

🏗️ Technical Architecture

Resound is a modern mono-repo designed for performance and scale:

• Desktop (apps/desktop): A Tauri v2 application (Rust/React) providing high-priority native audio capture and playback.
• Web (apps/web): A Next.js receiver that uses the Web Audio API for browser-based playback.
• Landing (apps/landing): A Next.js 15 + Tailwind 4 landing page with a modern "unearthly" aesthetic.
• Backend (Rust):
  • Axum: Powers the WebSocket signaling and binary audio distribution server.
  • CPAL: Manages native cross-platform audio streams.
  • mdns-sd: Handles local network service advertisement and browsing.

For an in-depth dive into the internals, see Implementation Details and Resound Shorts.

🛠️ Prerequisites

• Rust: Latest stable toolchain.
• Node.js: LTS version (v20+ recommended).
• macOS Requirements:
  • BlackHole 2ch for "Perfect Sync" mode.
  • Resound automatically attempts to create and manage the Resound Audio aggregate device.

🚦 Getting Started

Installation & Development

# Clone the repo
git clone https://github.com/princecodes247/resound.git

# Install dependencies
npm install

# Start the full stack (Desktop + Landing + Web)
npm run dev

Building for Production

# Production build for the desktop client
npm run build:desktop

🎧 Usage

Broadcasting (Host)

1. Launch the Desktop app and select "Broadcast" mode.
2. Choose your Sync Mode (Perfect or Lightweight).
3. Tap the Power button to go "On Air".
4. Share the provided QR code or Session ID with listeners.

Listening (Receiver)

1. Open the Web Client or another Desktop instance.
2. The host will appear automatically in the "Available Broadcasts" list.
3. Tap "Connect" to start the synchronized audio stream.

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Built with ❤️ by the Resound team. Designed for musicians, gamers, and audiophiles.