I think I already asked this a while back but never got an official reply: the ac30tb preamp cf defaults to a quite high value, while the ac30hot (technically the same amp with tone stack bypassed) defaults to 0.. is that correct or is that a mistake? Is the cf related to the tone stack, and that explains why for the hot model is at 0?
Is the Matchbox D-30 a CF amp? I'll play with the parameter and use my ears, but I sometimes have a hard time picking out the subtle changes, especially if it's in one of my tinnitus frequency bands.
You can tell if an amp has a cathode follower if the CF Comp value is nonzero.