I got my Standard three years ago on firmware Rev. 3.18. I've made use of all of the advanced parameters at one time or another. I won't use the word "tweak," because in the TGP mindset that connotes endlessly messing around with things you don't understand. When I make a change to a parameter, advanced or basic, I have an idea of the change it will produce, and I know what I'm looking for when I make the change. My "tweaking" consumes far less time than my practicing.
All of the advanced parameters correspond to design variables that an amp designer should consider, and they all have predictable effects on the sound and feel of the amp block.
Here are some examples of the advanced parameters I use most frequently:
1. Damp (negative feedback) - this defaults to zero in the Class A and related sims. Increasing it from zero cleans up the sound at lower levels and sharpens the transition to power section overdrive. If you push it too far, you get a really nasty-sounding overdrive that occurs abruptly as you cross the threshold between linear and nonlinear operation.
2. Sag (power supply impedance) - think of it as clean compression. It affects feel as much as - perhaps more than - sound, and I use it primarily for that purpose.
3. Lo Cut frequency (input highpass) - I use this one in almost all of my presets, and I always increase it from the default value. This is the most effective way to get rid of farty bass while retaining the basic tonality of an amp sim. If the sound is too thin after cleaning up the bass, just select a cab sim with more bass. Simple and effective.
4. Tone stack parameters (type, center frequency, location) - incredibly powerful tone-shaping tools. For example, my go-to clean preset uses the Class A (Vox AC30) sim with a Plexi tone stack placed in the "post" position. If a sim sounds too muddy or low-middy, I just find the tone stack center frequency that lets me dial it out.
5. Lo and Hi Freq Resonance (power transformer configuration) - I use mostly the Hi to fine-tune the amount of "glassiness" in the sound.
I use other advanced parameters, but I find the above the most useful and effective in getting the amp sounds (and feels) I want. I would not have kept my Axe-Fx without those parameters.
Last edited by Jay Mitchell; 10-21-2010 at 10:02 PM.