Microphone bleed, lots of overdubs (especially vocals), and repeated re-layering tracks on tape over and over due to channel limitations. They really were doing crazy stuff with limited tech.

I think this would be hard for bands that really fill the spectrum and don’t have that clean treble, mid, bass separation. Or recordings really compressed into a frequency range.

Now this makes me want to see what happens with like My Bloody Valentine and Husker Du :).