A question on pulse conditioning implementation
At minimum, you would need a selector switch, or some means of telling your "pulse conditioner" what input to expect. Otherwise your "pulse conditioner" would have to be an anticipatory system (which isn't going to happen).  

Envision the simplest op-amp comparator with a switch to select different threshold voltage to determine low and high levels, as a minimum system. The op-amp would have to use power rail of at least 12 volts, to accommodate your highest voltage input.