I recently bought a Fender Champ (silverface). I read that Clapton recorded the Layla record with a Tweed Fender Champ. What makes a tweed amp stand out? Are they wired differently?
I can only speak on limited tweed experience with my tweed '59 Bassman. As a player/performer I feel like the tweed cabinet is like an instrument unto itself. It is an organic, "living," breathing part of the whole tone equation. With my tweed I notice that I can work with the amp to create tones that I just don't quite get with my MusicMan 112 Sixty Five blackface. I've owned browns (early '60's Brown Tolex Super) and blackfaces. When I discovered my tweed Bassman, I knew it was my main amp for the rest of my life.
I've found that loose bottom end issues are more due to speaker problems than the circuits themselves.