I've tried various treatments, tweeks
On CDs over the years, going back to the unfortunate Armour-all incedent. I tried the one from Audience-got it free, and was worth every penny. I don't don't do any treatments any more. There are several things I've learned from trying treatments:
1) They tend to be a pain in the butt to use.
2) They do *change* the sound.
3) The change is NOT always for the better.
4) The change is rarely predictable
and last and most importantly
5) NEVER DO A TWEAK OR TREATMENT THAT YOU CANNOT UNDO!!!
Going back to the Armour-All fiasco, it worked, but clouded in time-I had already treated a hundred discs or so by then-I had to rub it off all of them-I was not amused.
With the Audience Auric-Illuminatior, I found that roughly 1/2 the time it improved the sound, the other 1/2 sounded worse-much worse. That comes off with soap and water. I pitched it. The only tweak I like now, is the old Navcom rings that fit on the edge of the disc by Sims/Sumiko, but they stopped making them years ago.
enjoy,
Jack