Many "line level inputs" actually run through the microphone preamp. If the topology of that preamp is a culprit to a nasty sound, it is a crap shoot as to whether a different preamp will help or not. Often, bad topologies reveal themselves most when boosting signals (something they don't have to do with a line level signal feeding it).
So, it really depends.
If you are not happy with your sound, and you are asking this questions, I suspect that you probably have MANY other things to learn about recording that can have a HUGE impact on your results.