Ardour 
Ardour is an open-source digital audio workstation which is used to mix, edit, and record audio and then share it with connected devices. In the beginning, Ardour was only available for Linux and macOS as it wasn't able to work on Windows systems. Later on, after improvising the software, it is now capable of working on Windows OS as well. It has a user-friendly interface with lots of graphics along with the option to change themes according to the user's comfort. This software allows the user to add more plugin variations along with the default and built-in plugins. 
 

Why you must get it: 
This software leverages original hardware which basically uses the computer for making music. This has a tabbed user interface bringing the editor window, the mixer window and all other preferences tabs within the same window. This application typically supports control masters like VCAs. It has unlimited music track playing features along with multiple mixing of audio at the same time and  has a record on tempo ramping too. Lua scripting from this software allows the user to make it their own by adding new features with manual scripts. It has integrated side chaining and pin connection points as well. Even the inline plugin display is merged in the same working window. Th is application enables the user to create non-destructive, non-linear editing with unlimited undo and redo options throughout the editing sessions. This has the best working mode with overlapping regions, and transparent and opaque regions.