JUCE is an open-source cross-platform C++ application framework for desktop and mobile applications, including VST, VST3, AU, AUv3, LV2 and AAX audio plug-ins.

C++ Audio Plug-in Framework for desktop, mobile and web

Audiobook Manager for Audible Users

Source code for SonoBus, a real-time network audio streaming collaboration tool.

Convert Audible aax files to mp3 and m4a/m4b

Convert Audible's .aax filetype to MP3, FLAC, M4A, or OPUS

Enhanced version of Cockos' iPlug - A simple-to-use C++ framework for developing cross platform audio plugins and targeting multiple plugin APIs with the same code. VST / VST3 / Audiounit / RTAS / AAX (Native) formats supported. NOTE: THIS IS OBSOLETE, PLEASE SEE IPLUG2:

A user interface toolkit mainly for audio plug-ins

DSP servers using general purpose computers and networks

Audio plugin framework. VST2/VST3/AU/AAX/LV2 for Linux/macOS/Windows.

Various resources related to developing plugins for audio production.

A command line interface for audible package. With the cli you can download your Audible books, cover, chapter files.

Converts aax to audiofiles online. Please don't sue me amazon.

Vaporizer2 hybrid wavetable additive / subtractive VST / AU / AAX synthesizer / sampler workstation plugin

The Open Source Audible Converter

Fast Audible AAX to M4A converter

Audio plugin that lets you use MIDI to pitch-shift via delay to turn unpitched audio into melodies

Decrypt Audible aax and aaxc files.

Audible audio book converter which actually works!

Plug-in allowing you to control the polar pattern of your OC818 microphone in up to five frequency bands. Developed by Simon, Thomas, IEM, and AA.