List of Intresting software and tools

Wavelab - One of the best mastering software.
TouchDesigner - a visual programming language and development platform, primarily used for creating real-time interactive multimedia content and applications

AATranslator2 - A comprehensive session file conversion program for the audio and video industries. It allows you to convert sessions between one DAW and another, and between DAWs and NLEs. This flexibility is liberating since you can now work in your favourite DAW/NLE without worrying about compatibility and you can also use the program which is most suitable for the task. With AATranslator you can accept or send session files in virtually any format. All this is good for creativity and helps get better and faster results.

Plugindoctor - A cross-platform and cross-bitformat plugin analyzer for VST and AU plugins. Whether you are a plugin developer yourself who wants to thoroughly test the audio quality of your latest and greatest product, or a power user who wants to understand in more detail what exactly a specific plugin is doing to your precious audio material, Plugindoctor will help you find out!
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Signalizer - is a all-in-one signal visualizing package with a bunch of unique focus-points; real-time audio visualization with optimized 3D GPU graphics, everything being scalable and zoomable gridlessly as well as being arbitrarily precise in both settings and display. Combined with a rich feature set, Signalizer is suited both for electrical/audio engineers fullscreen-inspecting signals, or for general small windows giving an overview of your audio as you create it.

Music Theory Site
hook theory
Plugdata - A visual programming environment for audio experimentation, prototyping and education