Voxengo SPAN Plus

SPAN Plus is a real-time “fast Fourier transform” audio spectrum analyzer AAX, AudioUnit, and VST plugin for professional music and audio production applications.

SPAN Plus is an extended version of the freeware SPAN plugin: SPAN Plus provides several additional features such as PNG file export, real-time spectrum import/export for multi-track spectrum comparisons, static spectrums display, and a “wide” display mode.

SPAN Plus provides you with a very flexible “mode” system which you can use to setup your spectrum analyzer preferences.  You may specify Fourier block size in samples, FFT window overlap percentage, spectrum's visual slope.  Beside that you can choose to display secondary spectrum of a desired type (e.g. real-time maximum, all-time maximum).  Spectrum can be smoothed out visually for an easier examination.

Beside multi-track spectrum comparison, SPAN Plus supports multi-channel analysis and can be set to display spectrums from two different channels or channel groups at the same time.  Spectrum's color can be chosen to taste.

SPAN Plus also features output level metering with adjustable ballistics and integration time, EBU R128, K-system metering (including calibration K-system metering).  SPAN Plus displays level metering statistics, headroom estimation, and clipping detection.  Correlation metering is available as well.