If a X50 comparison is performed, I would like the real amp to be a 6505+ because it's not a 6505 simulation 
(to get a fair comparison)
The "red channel mod" was implemented to get it closer sounding to the 6505, but it's still not a simulation of that amp
(to get a fair comparison)The "red channel mod" was implemented to get it closer sounding to the 6505, but it's still not a simulation of that amp
