Echos of hatred seem like they're from legendary refinement tributes!

Hey all, I've seen people posting about the drop rates on the Echos of hatred. I've noticed a high drop chance doing the refinement tributes (legendary) from the undercity. In 12 tributes I've had 5 Echos! Playing on torment 12, I don't know if that makes a difference.

I'd love to see if people are getting the same or if this was a string of good luck