Spectrum

Free GPU accelerated cross-platform audio spectrum analyzer.

spectrum.mp4

Features

• Real-time FFT-based spectrum analysis with thread safety built in
• Logarithmically spaced bands
• Spline interpolation to produce visually pleasing smoothed graphics
• Auto-calibration to ensure consistency
• Customizable frequency weighting
• Parameters can be changed on-the-fly, making it easy to dial in the right settings for your project
• Level ballistics controls
• Normalized output that allows easy integration into any 2D graphics library

Download

Grab the latest installer for your platform:

• macOS (arm64, VST3 / CLAP / AUv2): Spectrum-macOS.pkg
• Windows (x86_64, VST3 / CLAP): Spectrum-Windows.exe
• Linux (x86_64, VST3 / CLAP): Spectrum-Linux.tar.gz (Tested on Ubuntu 24.04)

See the Releases page for release notes and older versions.

macOS users: Since the installer is not notarized by Apple, Gatekeeper will block it on first launch with a "Spectrum-macOS.pkg Not Opened" message — this is expected and not a sign of a problem with the file.

To proceed:

1. Click Done on the warning dialog.
2. Open System Settings → Privacy & Security.
3. Scroll to the Security section — you'll see a message about the blocked installer.
4. Click Open Anyway, then confirm by clicking Open Anyway again in the dialog that appears.

You'll only need to do this once per download.

Build Requirements

macOS (arm64)

No special requirements needed, just a cmake build environment.

Windows (x86_64)

You will need to follow the instructions in the README at https://github.com/tadmn/FastFourier to install the Intel IPP library files. These library files are used for the Intel IPP FFT.

Linux (x86_64)

You will need to follow the instructions in the README at https://github.com/tadmn/FastFourier to install the Intel IPP library files. These library files are used for the Intel IPP FFT.

You will also need to install the following dependencies:

sudo apt-get update
sudo apt install libgl1-mesa-dev libxrandr-dev

Using in Your Own Project

The brains of the analyzer are in AnalyzerProcessor.h. The easiest way to use this is to copy the class .h/.cpp files to your project and then link with the required dependencies. See spectrum-analyzer-processor target in CMakeLists.txt for the list of dependencies. You can then feed the output into your own graphics library of choice. There is an example in the comments at the top of AnalyzerProcessor.h that shows how this can be done.