dbPoweramp is a sound file format converter (eg wav to mp3 or vv) - An audio editor lets you change the audio itself... - BTW, I second the Audacity choice. Especially with the Nyquist programming interface. I also use Cool Edit 2000 and Goldwave. CE2k is great for all sorts of editing and manipulating sounds (eg noise reduction), but unfortunately it's no longer available. Cool Edit Pro is, under the name of Adobe Audition (Bought by - guess who...) Goldwave is good for generating weird noises and stuff.
regards, Nils