Qtractor is an Audio/MIDI multi-track sequencer application written in C++ with the Qt framework. … https://www.tromjaro.com/qtractor/
MIT is a graphical utility for tuning your musical instruments, with error
and volume history and advanced features like microtonal tuning, statistics,
and various views like waveform shape, harmonics ratios and real-time Discrete
Fourier Transform (DFT). All views and advanced features are optional so that
the interface can also be very simple.