WMA has to work in the same sort of way. Thats how compression works.
MP3, the highest you can go is 320kbs and this is enough for any audio enthusiast, not being able to tell at all. Even 19kbs isn't bad.
WMA is really bad for low quality, but tends to get better as the quality goes up. MP3 is good all round.
The higher up in MP3 you go, the less compression and so less frequencies will be taken away. You can't hear what they take away at the higher settings