Audacity

Recording

Audacity can record live audio through a microphone or mixer, or digitize recordings from other media.

Export / Import

Import, edit, and combine sound files. Export your recordings in many different file formats, including multiple files at once.

Sound Quality

Supports 16-bit, 24-bit and 32-bit. Sample rates and formats are converted using high-quality resampling and dithering.

Plug-ins

Support for LADSPA, LV2, Nyquist, VST and Audio Unit effect plug-ins. Effects can be easily modified in a text editor – or you can even write your own plug-in.

Editing

Easy editing with Cut, Copy, Paste and Delete. Also unlimited sequential Undo (and Redo) in the session to go back any number of steps.

Effects

Real-time preview of LADSPA, LV2, VST and Audio Unit (macOS) effects. Plug-in Manager handles plug-in installation and addition/removal of effects and generators from the menus.

Accessibility

Tracks and selections can be fully manipulated using the keyboard. Large range of keyboard shortcuts.

Analysis

Spectrogram view mode for visualizing and selecting frequencies. Plot Spectrum window for detailed frequency analysis. Support for Vamp analysis plug-ins.

If you want to remove the nosie from an audio file, or level the audio, or basically do any kind of editing to an audio file, then this is the best application for both professionals and non-professionals.