I often use the pasteurized whites in the carton. On the side it says 1 large white is equal to 3 tbsp and 3/4 c is equal to 4 large whites. I just separated 4 large eggs and I got a little over 2/3 cup (a little less than 3/4). 4 extra large would probably be a full 3/4 of a cup. Either way, close enough!
2/3 of a cup is 10.6 tablespoons. 1/2 cup is 8 table spoons. If one white is about 3 tablespoons, then you need 1/2 cup plus 1 tbsp. to equal 9 tbsp
Bought the carton today to try out a Kahlua SMBC. The carton didn't have a measurement for the whites. Glad I found this old post on CC. Posting here so I can refer back to it later.