Summary

Kern Audio Check is a free real-time spectral mono compatibility analyzer available as a VST3/AU plugin for PC and Mac. It helps users identify frequencies that lose presence or collapse when summed to mono, providing detailed frequency band analysis rather than a single summary value.

Features

• Spectral Correlation Curve: Displays mono compatibility across 40 frequency bands in real time, showing where the stereo image holds or fails.
• Bass-Weighted Score: The analyzer weighs low frequencies three times more heavily than high ones to emphasize the importance of bass in mono compatibility, with an alert if bass drops below 60% indicating weak performance on club systems.
• Frequency Focus: Users can zoom into low, full, or high frequency ranges to isolate bass mono compatibility or inspect stereo highs specifically.
• Instant Mono and Side Monitoring: The MONO button collapses audio to mono to hear compatibility issues directly, and the SIDE button isolates the difference signal — the part lost in mono.

System Requirements

Compatible with macOS 12 or newer on Intel or Apple Silicon and Windows 10 or newer 64-bit systems. Requires a VST3 or AU compatible host.