SPAN is a free real-time audio spectrum analyzer plugin designed for professional sound and music production. Compatible with AAX, AudioUnit, and VST formats, it offers high precision analysis using fast Fourier transform technology. The plugin's flexible mode system allows users to customize spectrum analyzer settings including Fourier block size, FFT window overlap, and visual slope of the spectrum. These options enable detailed and adaptable spectral examination, making it easier to analyze audio signals in various production environments.

The plugin supports multi-channel analysis, allowing simultaneous display of spectrums from different channels or channel groups. Users can select colors for the spectrum display to suit their preferences and enhance visual clarity. Additional features include secondary spectrum display options such as real-time maximum or all-time maximum, and visual smoothing of the spectrum for improved readability. This level of customization helps producers and engineers focus on critical audio details during mixing and mastering.

Beyond spectral analysis, SPAN includes comprehensive output level metering with adjustable ballistics and integration time. It supports industry-standard metering systems like EBU R128 and the K-system, including calibration options. The plugin provides detailed statistics such as headroom estimation, true peak detection, and correlation metering, which are essential for maintaining audio quality and preventing clipping. Additional conveniences include preset management, undo/redo functionality, A/B comparisons, and support for all sample rates with high-resolution user interface scaling.