What are some alternatives?
When comparing Free Audio Editor and SoX, you can also consider the following products
DarkWave Studio - DarkWave Studio is a free, open source, Digital Audio Workstation for Windows.
Amadeus Pro - #
Adobe Audition - Mix, edit, and create audio content in Adobe Audition CC with a comprehensive toolset that includes multitrack, waveform, and spectral display.
SampleTank - THE MASTER-QUALITY MIDI SOUND MODULE AND GROOVE WORKSTATION FOR THE MOBILE ARTIST.
WaveShop - Open source audio editor
Spectro - Spectro is a freeware audio file analyzer for windows.