Grab yourself a nice audio interface. Plug in a microphone or a keyboard. Import audio or MIDI from your hard drive or the Freesound database. Cut, move, stretch, copy, paste, delete, align, trim, crossfade, rename, snapshot, zoom, transpose, quantize, swing, drag, drop. All with unlimited undo/redo. All in the same window.

Mix, mute, solo, fader, automate, EQ, dynamics, insert, send, pre-fader, post-fader, sync, monitor, isolate. Floating point fidelity, the most flexible mixer architecture in the industry, hundreds of plugins and external control surfaces.

ardour.org
community.ardour.org/download
Plugins
en.wikipedia.org/wiki/Ardour_(software)