Audacity - Audacity is a free and open-source audio production software suite that includes a surprising array of editing tools and recording systems.
GarageBand - GarageBand is a fully equipped music creation studio for Mac
Acoustica - Acoustica is an audio editing tool for editing, mastering and restoration work on both Mac and PC.
Adobe Audition - Mix, edit, and create audio content in Adobe Audition CC with a comprehensive toolset that includes multitrack, waveform, and spectral display.
Reaper - Reaper is a focused digital audio workstation (DAW) developed by Cockos. In the creation of the software, the digital audio technology company intended to make audio editing accessible to the masses.
AVS Audio Editor - AVS Audio Editor enables user to apply various effects and filters like cut, join, trim, mix, delete parts, split audio files.