I have 2 of the original Guv'nors and there is a noticeable tonal difference between them. I think Marshall revoiced them when production moved from England to Korea and added a bit more bottom end - I don't think it's just variation between components. I also have a Drivemaster and that sounds pretty different to the Guv'nors and lacks that je ne sais quoi the Guv'nors have. It's a while since I've used the Drivemaster so sorry to be so wishy-washy in the description

When I get a bit of time I'll have a look at the boards