If you have searched for this term, you are likely looking for one of three things: the history of the simulated hardware, a technical review of its DSP accuracy, or simply the perfect tone settings for your next mix.
You are likely using the "Crunch" channel with the bass turned up. Fix: Turn the Bass knob to 2 or 3. EQ in the mix, not in solo. The bass comes from the bass guitar, not the guitar track. overloud th3 345
Here is why, and how to fix it.