The manual says that tweed and ch2 has less reverb than the others modes/ch, someone here posted something about the mkv spring reverb, a mod or a replacement so the reverb in the mk would be stronger..anyway, its like the ch2 was build for rythm so you dont want a ball of guitar sounds and reverb, and ch3 for soloing and there you can dial in more reverb..but I use ch3 for rythm and without eq for soloing too..in ch2 crunch and edge are more reverb friendly than the mark1 mode lol