WavePad is a very interesting program that allows you to perform multiple actions on your sound files. With it you can copy, cut and modify an audio sequence as you wish.
The graphical representation of the sound wave greatly facilitates working with files. Some of the transformations that can be made are: amplify, normalize, equalizer, reverb, echo, fade in and fade out, envelope, noise reduction, etc. Also, it allows you to change the speed and pitch of an audio stream in three different ways.
WavePad includes other very interesting tools, some of them are not available from the beginning, but you can download them for free from the author’s page. It is a tone generator and a speech or ‘text to word’ synthesizer. Furthermore, with this program you can create batteries of actions to simplify work with multiple files.
The formats it supports are WAV, MP3, WMA, VOX, GSM, AU, RM and some more. Lastly, it accepts samples from 6000 to 96000Hz, stereo or mono, 8, 16 or 32 bits.