I'm trying to repair a song from a CD recorded in ~1997 that isn't of the best quality initially on the CD. Doesn't help the song was a "demo" performance at the time so didn't have all the extra TLC normal tracks would have. I've been working with it in Audacity trying to clean it up, and for a nub at it I'm not doing too bad, but I'm trying to remove this very audible "hiss" and having problems. It's just a constantly audible airy sound, and sometimes it will get larger when multiple tracks are layered causing the hiss to double up. I believe they were all originally recorded on tapes which might be causing it? The only way I've found so far to get rid of it is to do a Low Pass Filter, but then seeing how it's all piano/synth I end up losing some of the high end on the piano. I've never worked with songs like this before so any advice/help is appreciated.

If anyone wants to try and "repair" it themselves PM me and I can give you a link to the song. It's Vince DiCola's "Training Montage". A hidden song on "The Protoform Sessions" from BotCon 1997 (I think) in case anyone is curious. I intend to "fix" all of the songs from the "'Till All Are One" 3CD set (huge TF:TM nerd), but gotta figure this hiss problem out first.

Btw, "Artistic Expressions" fucking owns if you like the old TF movie score. I'll put a link to the official store that sells it in case anyone wants it cause it took me forever to find it digitally much less a legit actual CD for order. You can also get rare Buckethead albums on there I am told. Anyway thanks in advance for any help/advice.

Official site to order "The Protoform Sessions" and "Artistic Transformations":
http://travisdickersonmusic.com/stor...e_catalog.html