procedural texture to only b/w

Is there any way to make (internally in Blender) procedural voronoi texture convert to only black/white not grey shades.
Reason for this is to do displace map

Just add a colorband to the texture. In the colorband you set one color to black and another to white. Then you move them very close to each other. The closer you move them together the sharper the edge between black and white. In the limit you will only have black and white.

That is it! Thanks!