Two part question. First part: I'm fairly new to bass having played guitar most of my life. I reckon I could recognise the tone of most guitar amps blindfold - they either fall into the Marshall, Fender or Vox tone camp. Those are the three seminal tones (IMHO). I have very little experience with bass amps. I am playing through an Ampeg PF500 and find it more than capable and pleasing for the low bedroom levels I play at. But here's the question - yesterday I read a post about someone who had switched from Ampeg to an Orange Terror Bass and was loving the amp giving him everything he wanted 'without the Ampeg tone' and its not the first time I've read things like this. So it seems there is something about the 'Ampeg tone' that people either love or hate and I'm at a loss to detect that myself. I know its not the easiest thing to describe tone in words but give it your best shot - what is it about the 'Ampeg tone' that divides people.
Second part to my question: If, as I think guitar amps can be roughly divided into the Fender, Marshall or Vox camp in terms of tone, is there a similar distinct group of tones that bass amps fall into?