Hello! as3sxfr is a free open source tool for generating sound effects, primarily for games but they could be used for anything you like! It's quite an old tool now though, why don't you give my new sound toolChipTone a try?
All sounds created using as3sfxr are FREE to use for any purpose, commercial or otherwise, under theCC0 licence. However, if you'd like to, you can donate below!
as3sfxr was ported from sfxr in 2010 by me, Tom Vian. You can reach me attom@sfbgames.com or@SFBTom, and find my games atSFB Games.