apparently these amps can use KT88s without being modded at all, only need to be rebiased. pretty cool video with great audio. doesnt really show the amp doin anything brutal, but does get fairly heavy. has a really nice warm tone too, seems to have a nice thickness in the lower mids. i can tell that this amp with the right settings and right guitar/pickups is definitely capable of some good metal tones. id like to hear it with a 7 string. i really liked the fact that the guy in the video showed what the amp sounded like with and without the overdrive pedal/pedals everytime he changed the amp settings.