To me, At The Gates' With Fear I Kiss the Burning Darkness became somewhat unlistenable some time ago due to its really annoying production. That was when I started experimenting around with Winamp equalizer settings to mitigate the impact of bad production.. with quite satisfactory results.
I've gotten into the habit of creating eq settings for any album whose sound I don't like enough. Here's a sample of what I've made:http://www.megaupload.com/?d=NRQWV09L
These are equalizer files for Winamp 2/3/5. Load with Presets -> Load -> From EQF (for Winamp5)
Album settings inside for:
Amorphis - The Karelian Isthmus
ATG - With Fear I Kiss The Burning Darkness (huge improvement, try it!)
Atheist - Unquestionable Presence
Bathory - Blood Fire Death
Demigod - Slumber Of Sullen Eyes
Enslaved - Vikingligr Veldi
Therion - Beyond Sanctorum
If you get overpeaking (crackling sounds), decrease the "Preamp" value.
If you know of other ways to get more out of badly produced albums, don't hesitate to post them.