Jay Mitchell
Fractal Fanatic
Having bought into the entire concept of the Axe-Fx as not being a "modeler" in the commonly-understood sense of that word, and furthermore never having been able to stand the sound of any overdrive pedal I've ever tried - including boutique-modded versions of various "classic" drives - I've never given the subject a lot of thought. I will say that, with the drive block parameters that Cliff has exposed in recent FW updates, the motivated user should be able to get whatever sound (s)he wants to hear. I've now used a drive block to effectively add a gain stage - with associated tonal shaping and level controls - to the input of a tube amp model. This adds a tremendous range of saturation/overdrive characters to that already available from the amp block alone, and it mirrors a set of mods I performed on a Marshall 50W combo ca. 1983.
Contrary to a prior assertion in this thread, the "physics" of physical drive pedals are accounted for in the Axe-Fx, with one exception: the input impedance presented by a pedal may be quite different than that imposed by the amp (i.e., when the pedal is bypassed). Given the above-referenced design philosophy, this is a Very Good Thing, as guitars are very finicky about the load impedance they see, and the most common tube amp input stages do as good a job of optimizing this (1Mohm impedance) as is possible. The Axe-Fx input impedance is the same 1megohm value as most tube amps. If you wish to add a more "realistic" loading effect than the Axe-Fx produces, you can produce same with about $15 worth of parts (which includes a really nice housing) or spend several times that on a Radial Dragster.
If you have a specific sound in mind, you can use the tools that are already there to get that sound. I would only use the "model" approach as a starting point.
Contrary to a prior assertion in this thread, the "physics" of physical drive pedals are accounted for in the Axe-Fx, with one exception: the input impedance presented by a pedal may be quite different than that imposed by the amp (i.e., when the pedal is bypassed). Given the above-referenced design philosophy, this is a Very Good Thing, as guitars are very finicky about the load impedance they see, and the most common tube amp input stages do as good a job of optimizing this (1Mohm impedance) as is possible. The Axe-Fx input impedance is the same 1megohm value as most tube amps. If you wish to add a more "realistic" loading effect than the Axe-Fx produces, you can produce same with about $15 worth of parts (which includes a really nice housing) or spend several times that on a Radial Dragster.
If you have a specific sound in mind, you can use the tools that are already there to get that sound. I would only use the "model" approach as a starting point.
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