mp3s are for lovers
I just tried an interesting visual experiment: load a WAV of a file and an MP3 of a file into Soundforge or Peak or any audio editor, and cue them up to the same place. Then zooooooom in, and compare the waveforms. Eventually, at high enough levels of zoom, you’ll start to notice differences in the waveforms.
Then, try drawing in changes to one of the files, and see how much you can distort the waveform without your ears noticing it. Sound is a shifty, shifty thing…