PluginBridge - Low-Latency LAN Audio Bus & Patchbay

PluginBridge is a high-performance, real-time JUCE-based audio plugin and standalone application inspired by Audiomovers OMNIBUS 3. It allows you to route multi-channel audio between DAWs across 2 or more computers on a Local Area Network (LAN) with ultra-low latency, zero configuration, and crystal-clear fidelity.

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Key Features

• Multi-Computer LAN Audio Routing:
  • Connect two or more DAWs (Ableton Live, Logic Pro, Pro Tools, Reaper, Cubase, Studio One, FL Studio, etc.) across physical computers via Ethernet or Wi-Fi.
  • Supports up to 48 input and 48 output channels per instance (2,304 crosspoint matrix router) with simultaneous bidirectional streaming.
• Zero-Config Auto-Discovery (mDNS / Multicast Beacons):
  • Plug-and-play operation using background UDP multicast beacons (239.255.77.88:52800).
  • Automatically identifies hostnames, instance aliases, IP addresses, listening ports, channel counts (up to 48ch), and active streams on the network.
  • Includes manual IP/port entry for enterprise routers that block multicast.
• Low-Latency UDP Streaming Engine:
  • Lock-free, real-time safe audio thread architecture (juce::AbstractFifo / ring buffers).
  • Configurable packet payload sizes (64, 128, 256 samples) enabling sub-5ms LAN transmission over 1GbE Ethernet.
  • Uncompressed 32-bit float bit-perfect transmission with generous 4MB socket buffers.
• Adaptive Jitter Buffer & Hardware Clock Drift Compensation:
  • Automatically compensates for unsynchronized physical audio hardware clocks between different computers (e.g. 48000.005 Hz vs 47999.992 Hz).
  • Employs a closed-loop PI controller tracking buffer occupancy coupled with Catmull-Rom cubic fractional resampling to smoothly adapt the sample rate with zero audible clicks, pitch jitter, or pops.
• Direct Physical Audio Interface Channel Selection & Remapping:
  • Remap any of the 48 matrix channels directly to physical audio interface hardware channels (e.g. IN 01 [IF 17], OUT 01 [IF 09]).
  • Interactive row and column headers in the patchbay: click or right-click any channel header to directly select its audio interface channel from grouped bank menus (1-16, 17-32, 33-48).
  • Quick sequential and bank offset presets (Offset +8, Offset +16, Bank 1 -> IF Ch 17-32, etc.).
  • Dedicated AUDIO IF MAP button and interactive 48-channel modal dialog for remapping all hardware channels at once.
  • Dedicated AUDIO I/O button in the header displaying host sample rate, buffer size, discrete 48x48 bus topology, and direct access to Standalone soundcard settings.
• Audiomovers OMNIBUS 3-Style Interactive Routing Matrix (48 Channels):
  • Clickable crosspoint matrix patchbay connecting DAW Inputs, DAW Outputs, LAN Transmit channels, and LAN Receive streams.
  • Bank Navigation & All-48 Overview: Switch between 1-16, 17-32, 33-48, and ALL 48 master matrix views with live crosshair guide beams and hover tooltips.
  • Clean, high-compatibility ASCII UI rendering with zero font glyph corruptions or broken boxes.
  • Real-time LED VU peak meters for all 48 channels with dB scale, peak hold indicators, and clip LEDs.
  • Quick action routing buttons (1:1 Patch across 48 channels, Stereo 1-2, Clear All, Thru monitor).
• Diagnostics Dashboard:
  • Live readout of LAN TX/RX bitrates (Mbps), packet loss percentage, jitter buffer depth, and hardware clock drift ratio.

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Architecture Overview

 Computer 1 (Control Room Mac)             Computer 2 (Synth / Mix PC)
┌──────────────────────────────┐          ┌──────────────────────────────┐
│  DAW (Ableton / Logic Pro)   │          │   DAW (Reaper / Cubase)      │
│  Outputs 1-16   Inputs 1-16  │          │  Outputs 1-16   Inputs 1-16  │
└──────┬───────────────▲───────┘          └──────┬───────────────▲───────┘
       │               │                         │               │
┌──────▼───────────────┴───────┐          ┌──────▼───────────────┴───────┐
│      PluginBridge (AU/VST3)  │          │      PluginBridge (VST3)     │
│  ┌────────────────────────┐  │          │  ┌────────────────────────┐  │
│  │ Interactive Patchbay   │  │          │  │ Interactive Patchbay   │  │
│  └───────┬────────▲───────┘  │          │  └───────┬────────▲───────┘  │
│          │        │          │          │          │        │          │
│       TX FIFO   RX FIFO      │          │       TX FIFO   RX FIFO      │
│          │        │          │          │          │        │          │
│       UDP TX    Jitter+Drift │          │       UDP TX    Jitter+Drift │
└──────────┼────────▲──────────┘          └──────────┼────────▲──────────┘
           │        │                                │        │
           ▼        │           LOCAL AREA NETWORK   ▼        │
           ═════════╧════════════════════════════════╧════════
                            Low-Latency UDP Packets

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Building the Project

Prerequisites

• macOS (Apple Silicon or Intel) or Windows
• C++20 compatible compiler (Apple Clang / GCC / MSVC)
• CMake 3.22+ and Ninja (or Xcode / Visual Studio)

Build Commands (macOS)

# Configure with Ninja and Release mode
.tools/cmake/data/bin/cmake -B build -G Ninja \
    -DCMAKE_MAKE_PROGRAM=.tools/bin/ninja \
    -DCMAKE_BUILD_TYPE=Release

# Build all targets (Standalone, VST3, AU, and test harness)
.tools/bin/ninja -C build

The built binaries will be located in:

• Standalone Application: build/PluginBridge_artefacts/Release/Standalone/PluginBridge.app
• VST3 Plugin: build/PluginBridge_artefacts/Release/VST3/PluginBridge.vst3
• AU Component: build/PluginBridge_artefacts/Release/AU/PluginBridge.component
• Test Suite: build/test_harness

Installing the Plugins on macOS

To make the plugins available to all DAWs on your system:

# Copy VST3 plugin
cp -R build/PluginBridge_artefacts/Release/VST3/PluginBridge.vst3 ~/Library/Audio/Plug-Ins/VST3/

# Copy Audio Unit (AU) component
cp -R build/PluginBridge_artefacts/Release/AU/PluginBridge.component ~/Library/Audio/Plug-Ins/Components/

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How to Route Audio Between 2 Computers

1. Insert PluginBridge:
   • Insert PluginBridge onto a track, master bus, or auxiliary send in your DAW on Computer 1.
   • Insert PluginBridge on a track in your DAW on Computer 2.
2. Auto-Discovery:
   • Both computers on the same LAN will immediately detect each other and show up in the Discovered LAN Peers list on the left panel.
3. Connect:
   • Click the green Connect button next to the remote computer in the peer browser.
4. Patch the Channels (Matrix Router):
   • On Computer 1: Select the DAW IN ➔ LAN TX tab, then click the matrix dots to route DAW channels (e.g. channels 1 & 2 or 1 through 8) to LAN Transmit channels.
   • On Computer 2: Select the LAN RX ➔ DAW OUT tab, then route the incoming LAN Receive channels into your DAW output tracks.
5. Bidirectional Streaming:
   • Both machines can simultaneously transmit and receive audio in real time with sub-5ms latency and full clock drift synchronization.