Just made three sloppy clips at: www.soundclick.com/bloos/ 1. Cleans 2. British 3. California CLEANS: The cleans has first track with guitar plugged into the line-in of the amp. If you observe the tone is slightly muddy and lacking in treble. The second track has guitar plugged into the guitar-in port. I deliberatly kept the mids high, to get a tone closer to the line-in. However if you notice, the bass and mids are still less than line-in, and treble and presence is more. BRITISH: Used TRI-AC on Plexi. First track is sansamp to the guitar-in. The tone has huge high-end. The low end gets removed. Second track is the same sansamp to the line-in port. Observe how the tone is more bassy and slightly muddy. CALIFORNIA: Same as above. Used the Boogie setting on the sansamp. Conclusion: the tone coloring section of guitar amp reduces the bass, removes the muddy mids, boosts the treble and presence. BTW, I kept the settings on teh sansamp exactly same. So that you can hear the huge difference.