The Extreme mode on the Mark V is based on the Lead Channel of the Mark IV with the presence knob pushed in. It lowers the negative feedback and makes the amp much more aggressive and louder. Set the new presence shift in the USA Lead models to off.
Thx, gotta try that. I was under the impression that the low frequencies were also increased compared to the Mark IV mode but i'm not too familiar with the originals of those amps.
BTW new firmware is amazing as always!