Spek

What Spek is

Spek is a desktop application for examining audio files through their spectrograms. It displays both a spectrogram and spectral density view, along with the codec name and audio signal parameters. Users can adjust the spectral density range and save a spectrogram as an image. Rulers for time, frequency, and spectral density fit automatically to the display, and files can be opened with drag and drop or through associations with common audio formats.

Spek processes audio offline and uses multiple threads to speed analysis. It supports popular lossy and lossless formats through FFmpeg libraries, and its interface is translated into multiple languages. The program runs on Linux, macOS, and Windows. It is free and open-source under GPLv3, with a Free software plan at no cost and no paid plans stated. The download page lists version 0.8.5 as latest and offers a BSD/GNU/Linux source tarball, Windows installer and archive, and macOS installer; the Windows and macOS installers are marked beta. The project invites bug reports and feature requests through its GitHub issue tracker.

Who it suits

Spek suits people who want to inspect audio files visually, check codec and signal details, or export a spectrogram image. It is intended for offline analysis on Linux, macOS, or Windows rather than real-time monitoring.

Limits

The Windows installer for version 0.8.5 supports 64-bit systems only. Its macOS installer requires Catalina or newer and is built for Intel CPUs; the maker says it should work with newer ARM chips. The Windows and macOS installers are marked beta.

Getting started

1. Visit https://www.spek.cc/.
2. Choose the download for Linux, Windows, or macOS.
3. For Linux, use the BSD/GNU/Linux source tarball; Windows downloads include an installer and archive.
4. Install the Windows version on a 64-bit system, or the macOS version on Catalina or newer.
5. Open an audio file by dragging it into Spek or using a common audio format association.

Verdict

Choose Spek for free, offline audio inspection with spectral views, signal details, and image export. Look elsewhere if you need real-time analysis; macOS users also need Catalina or newer for the listed installer.