what are compression settings as in setting compression with winamp plug-ins?

[joanne]

With Audiostocker and Rock Steady, both of which I use, there's a set 
compression area and one thing says like 18 db and then flat db or something, 
and another box says soft compression, hard or very hard.  What do all these 
things mean?  Is the sound more distorted with, say hard compression and what 
are the other boxes with the 18 db and flat db talking about?  What differs in 
the sound quality when changing settings?

Thanks for any help.

recommendations for a usb sound card with line in put?

[Hank Smith, and Seeing-eye dog Iona]

Hello my creative live usb sound card just died and am in need of a usb 
sound card, what does any one recommend for a inexpensive sound card 
with line input?

I see alot of them on amazon but none have line input just mic input
Hank