First example which comes in mind is I.F.O. Anyone not agreeing ? 
  
agree. 
  
I.F.O is also a perfect example that great music hasn´to be superclean/supermastered, to create positve feelings in us.   
  
I think, nowdays at the moment, its a crazy clean-mastering hysterical chasing in the studios. Sometimes is it good, like Son-Kite - Colours for example. But to often the "spirituality" in the tracks, albums are forgotten... 
  
We have this israeli "psytrance" which are clean, everything is at the same level, top-notch production.  I can´t see the spirit in that music. The same phenomena have now also went over to the proggressvie trance scen:(. What happended to Iboga, which have been one of my fav-labels? (this i my humble opinon) 
  
I think that I.F.O wouldn´t be better if the mastering was it. Maybe it would be more negative for the album? I think that all  mysterious tranceendental, up in the space sounds wouldn`t be present in the same grade, if the mastering were top-notch... 
  
Have a nice springday! // Yatha