WaveShop is a free, open-source audio editor. WaveShop is fast, lightweight, and bit-perfect, meaning samples aren’t altered unless they need to be. Editing a portion of an audio file only affects that portion; the rest of the file is untouched. Blocks of audio can be cut and pasted without changing their contents at all. This is especially useful for patching a finished master without corrupting its dither. Waveshop’s features include peak and RMS analysis, normalizing, fading, audio generation, and more, all with unlimited undo. WaveShop supports WAV, FLAC, MP3, OGG and other popular formats.
Source code:https://github.com/WaveShop/