-Adjustable bias control
-Master volume and PPIMV
-Adding extra speaker outputs
-Upgrading cables
A Master Volume modification can change the tone of the sound from quiet to loud.
If a Marshall was made to sound more like a Fender on clean, and more distorted like a Mesa, Marshall would have made it like that. There is a certain level of respect needed to be given in why amps have their function such as they do, the designers spend much time trying different drives, distortions, EQ to get it right for their signature sound.
