A lot of classic records would sound nothing like they do today without the compression applied in various stages.
Take for instance Nirvana's song In Bloom. Listen to the original release, then the remastered "best of Nirvana" collection (I think it was released around 2009 or something like that). It's not just the loudness war that changed that remaster but the actual compression used during mastering. The swing is lost.
.. or basically any disco track from the 70's, or soulful funk stuff from 80's. The way the music swings and every bar gets sort of underlined with an extra thud of power. A lot of the nuance is not just due to the skillful musicians involved, some credit goes to the compressor.
I find compressors absolutely fascinating.


