A few of us have already tried to chime in here, and on the other forum too. To echo what the others have said, There's no magic bullet. If the original recording is naff, well, there's a few tricks you do with eq and stuff. but if it ain't right in the first place, it needs doing again from scratch. For a home studio you need a decent PC/laptop, plenty of RAM, a good audio interface, a midi keyboard/controller, a good condenser microphone, and a DAW. I use Cubase but others here use Logic, Reaper, Studio One, Cakewalk and the rest. You mentioned Audacity. That's a great, free audio editor and it will record multitrack, but it isn't a proper DAW. To answer your original question..'Anyway to change poor recording quality to good?'...No.