I think barn doors would be wonderful! Of course, I have double french doors on my bathroom.

Cool idea. I have double glass doors on mine too, though.
Renee

You could put in barn sound effects with the door, that might solve the need for sound privacy :)

We've got them on our jack & jill bath. the toilet is in a separate room with a pocket door (assume that's what you're wanting to soundproof), so I can't help there.

If it's the 'flimsy' feel of regular pocket doors that you object to, please know that good doors (solid wood) and good hardware really to fix that problem.

If it's the barn door look you're after, I'd think insulating the walls and choosing a solid wood door would be plenty good enough.

And a bath fan would also help mask any noises...