Missing bass or my imagination?

[Ice P]

When I make up a flashdrive to play in the car, I usually end up with a mix of .wavs that were originally flac and some that were originally mp3. I'd swear the files that were mp3 are missing some bass and sub bass but it's hard to tell when I can't find original copies of the mp3s anywhere. Is there scientific evidence to back this up or am I imagining it?. BTW, I don't look at the track, see that it was originally mp3 then decide it sounds weak. What usually happens is, I find myself boosting the bass via the eq, still not being really happy, then realising it was one of the mp3 originals.

[Chad]

If you use a high bitrate MP3 then you should not hear that much of a difference, if any.

[MiniVanMan]

Like Chad said, if you have a high quality mp3 to begin with, you shouldn't hear a difference. Sounds like you don't have high quality mp3s, which isn't uncommon. I've had quite a few mp3's that were damn near unlistenable. Usually these were shared mp3s ripped on i386 computers back in the 1980's.