for one, the claim that this x, y or z's modeling product was designed specifically from circuits and components of those amplifiers and tubes and transformers it models. if that were the case, there would be no major change in gain or dynamics now would there?Most modellers will dial in more gain than the real amps. You can also dial the gain out. It always amuses me when people use this as an argument against them.... "It's not like the real amp, it can get more gain!". Sounds like an improvement.
how many 3 and 4 ch amps are modeled exactly as the real amp? if it were so and they were designed exactly by schematic, why don't they have all 3 or 4 ch's and their compliment of depth, specific eq, and other controls instead of just one sound emulating one channel of that amp? model an orange amp, and you have controls available not on an actual orange amp? then what is modeled by circuit design? what about a mark v or road king or amps with power options? if by exact circuit, yeah i would love to see a road king modeled exactly. there isnt enough menus to account for that amps options.
if modeling makers did not reference actual specific amps, then they wouldn't have as many people refuting. most modelers kind of sound like a recording of an amp, but then give you eq and gain parameters to adjust. when you take the gain down on most high gain models it gets real thin or sounds like your signal is fighting a gate even with no gate on.
i have not had one amp model ever sound like or behave like the real amp. its an emulation you can adjust and play through but all in all its just that an emulation. there are no 40 or 50 amps in that box. its one preamp. then you have to find means of amplification. so much for the power amp emulation. now you have power amps and speakers fighting the modeled emulations.
they sound good, but they dont replicate amps imo.