You guys might want to check out issue 7 of Vaccum tube Valley (VTV). An analysis of about 26 different versions plus a history of the development with pictures of versions from different eras.
In VTV has done such test on a number of tube types. I don't necessarily agree with any of them but it is basically what this thread proposed.
BTW-I think this endeavor is fruitless. You can change the sound of tube by just changing the operating point (plate voltage, load ressistors, heater voltage,...). Also, the sound in different topologies(anode follower, cathode follower, cascade, mu follower, etc..) vary with the same tube.
In VTV has done such test on a number of tube types. I don't necessarily agree with any of them but it is basically what this thread proposed.
BTW-I think this endeavor is fruitless. You can change the sound of tube by just changing the operating point (plate voltage, load ressistors, heater voltage,...). Also, the sound in different topologies(anode follower, cathode follower, cascade, mu follower, etc..) vary with the same tube.