Expression to affect by attribute with falloff/blur

Hey! I've been trying to use a mountain node to only affect the white parts of the Cd attributes but the expression "@Cd.r>.1" leaves a hard transition between the whites and the blacks of course.

Is there a way to make the mountain node affect by atttribute (with falloff/blur)

It would be easy in a point vop to just multiply the noise by the Cd attr but I can't manage ta achieve a similar displacement look as the mountain node.