Well I think I might know your problem. Your pick-ups. Jerry's Wolf has three single coil pick-ups while your SG has two humbuckers. The difference; well a humbucker has more power more crunch. It play's dirtier, rougher. While a single coil has a thinner HIGHER sound. A Fender Strat has single coils if you don't have a Strat you can buy a fine Standard of $430 from Musiciansfriend.com.
a preamp buffer usually brings out more highs and better clarity all around.
"The process of selecting the tone on the guitar is an aesthetic process like any other, so you try a lot of different things. Most of the things I’ve tried I’ve tried in live performances" ~ Jerry Garcia