mattsven471:
I think that a simple option is using comparators and a power supply with voltage you need.
But that will not shift the 0V level down will it? Sure it can shift the top level up as they have open collector outputs so you simply pull up the the required voltage but shifting the 0V is much more tricky.
You have to ask why the OP thinks he wants to do this.
When we find out we can point out the proper way to do what he wants to do.