Virtual Audio Cable (VAC) 4.71: Advanced Audio Routing & Virtual Device Software

Virtual Audio Cable (VAC) 4.71 is a professional software application that creates virtual audio devices on Windows systems, acting as a digital patch cable to route audio streams between software applications . Instead of relying on physical hardware connections, VAC uses a Windows WDM/KS kernel-mode driver to establish internal links where the output from one program becomes the input for another program.

First released in 1998, VAC has evolved through multiple versions and now supports Windows systems from XP through Windows 11, including ARM64 architecture. Each “Virtual Cable” consists of a pair of ports—input and output—that are internally connected. Audio data sent (played) to the output port by a source application is implicitly transferred to the input port and can be retrieved (recorded) by another (destination) application. It can create up to 256 independent virtual cables, supporting multiple simultaneous audio streams.

👥 Primary Users

  • Audio Engineers & Sound Designers routing audio between applications for live performances and complex studio setups

  • Content Creators & Streamers mixing system audio, microphone inputs, and application outputs for live broadcasts, podcasts, and streaming platforms like OBS Studio and vMix 

  • Software Developers & Testers creating virtual audio environments for testing applications that require audio input/output without physical hardware 

  • Music Producers & DAW Users integrating multiple software synthesizers, sequencers, and audio editors into a single workflow 

  • Voice & Telephony Application Users routing audio between VoIP clients (Skype, MicroSIP) and recording software or speech recognition tools

⚡ Key Features & Capabilities

 

🎯 Core Audio Routing

  • Virtual Device Creation: Creates virtual playback and recording devices that applications recognize like real sound cards 

  • Application-to-Application Routing: Directly sends audio from one program into another (e.g., player → recorder, mic → chat app) 

  • Low-Latency Transfer: Designed for real-time use, with minimal delay (under 1 ms when optimized) 

  • Multi-Client Support: Multiple applications can open each virtual cable port simultaneously; sounds are mixed together for playback, and each recording client receives an individual copy of the signal 

🔧 Technical Capabilities

  • Bit-Perfect Digital Audio: Transfers audio without quality loss, maintaining the purest possible sound 

  • Format Conversion: Supports PCM audio formats with sample rates from 1000 Hz to 384000 Hz, 8-32 bits per sample, and up to 32 channels 

  • Flexible Configuration: Customize parameters per cable, including sampling rate, bits per sample, channel number, and volume control 

  • Channel Scattering/Gathering: Remap audio channels between streams 

📦 Included Utilities

  • Control Panel Application: Configures cables and monitors their state 

  • Audio Repeater: Transfers audio from any recording device to any playback device, enabling routing between physical and virtual endpoints 

🆕 What’s New in Version 4.71

  • Windows 11 Support: Full compatibility with Windows 11, including x64 and ARM64 architectures 

  • Performance Optimizations: Improved stability and reduced latency for streaming and production workflows