musicalwarmth812 wrote:Thanks, but I am aware how amplification and gain stages work. Sure, not all 12AX7's are identical - different brands, NOS, etc. - but maybe you are trying to say a 12AT7, etc., is not a 12AX7.
You lost me with your last paragraph. Thermionik contains two modded JCM800 models, those two amps are not what I am referring to. I am referring to the stock 800 and the blue channel of Psycho C. You put those two amps side by side and A/B, there is no way the 800 has more gain. So even the Stock 800 is essentially modded here, I get it. Still doesn't explain how, at the same input voltage, that stock 800 has more gain than the Psycho C blue channel.
If you have real tube amps, different selections of preamp tubes can change the character considerably - have a look at Doug's Tubes for example - he provides selected tube sets for popular amps and you can also roll your own combinations.
I don't have a lot more to add but I am not sure what your issue is - you are correct that there is not a one to one correspondence between the gain controls and the input level control on these simulated amps and the real amps they are derived from. Is that actually a problem?