Over the last twenty years or so a lot of classic rock records have been remastered. I've bought quite a few of them myself and most of them I've felt were improvements like the "1990 Led Zeppelin Remasters". But some of them I thought sounded too compressed.
Rush has just remastered their album Vapor Trails because in the words of Alex Lifeson :
"The original version is hard on your ears, because the mastering was pushed so hard, there's distortion and so much compression