What does "bad tone" sound like?
Well, since you asked of personal opinion, and my preferences, well... bad. Sorry, I couldn't help myself, but it's bad by me.
Can't be put into words. I've tried numerous horrid basses that are set up poorly, and contains old strings, and hums, and whatnot, and more often than not, due to their bad setup I can't get a good tone out of them. Some basses are "tractors" sluggish and you have to really struggle to get ANY tone, bad or not. Then the net result is just bad tone. In or out of quotation marks. I even try to alter my style finger pick or do some ancient musical stuff of the 60s with the "muffler" sound that was on the j bass. No way, I just think it sounds like all of the bass has got "dead spots" although it isn't dead spots. It's the whole bass that's a one big large dead spot. Mostly was it eastern bloc cheap copies. And some early (very) japanese. But that's bad for me. If the bass hasn't got any obstacles in ergonomics, or intonation, set up, relief, action and pickups, and fairly fresh strings that keeps in tune, I don't mind it. Although Rickenbackers have their own tone and J or P basses have their own tone, I wouldn't state that any of them were particularly bad, since I can't stand playing Rics for ergonomic purposes. I e, just because someone ELSE can coax good tones out of a bass, It's not "bad tone" just because I can't play them.