Preamp bias default on fw 2.0X (question to fas)

[edo]

i just noticed that preamp bias in the ac30tb model goes from -0.6 to -0.02 to -0.4 depending on the modeling fw (although some of my presets made with 2.01 randomly default at -0.11). What would be the correct value according to actual measurements of the amp?

 

[Starfighter]

Just noticed this as well. Haven´t played around much with preamp bias before (I'm quite the noob on advanced amp parameter), it sure has a noticeable impact on the sound of the AC30-model. In my U2 presets I find that I prefer the -0.02-setting.

 

[edo]

Just noticed this as well. Haven´t played around much with preamp bias before (I'm quite the noob on advanced amp parameter), it sure has a noticeable impact on the sound of the AC30-model. In my U2 presets I find that I prefer the -0.02-setting.

I guess thats why i like 2.01 better as well, but i'm just curious to know what's the "correct" setting - there must be a reason if the latest fw has it at -0.4!