I brewed EdWort's Haus Pale ale this weekend exactly as he has it listed in his thread. In his thread, it says it should be 39 IBUs with a 6.5 gallon pre-boil volume and a 5.5 gallon final volume. When I enter this recipe into BeerSmith2 it gives me 31.2 IBUs. I noticed when you change the 'equipment' option it changes the IBUs. Why would the pot have any effect on the IBUs if you still have the same pre and post-boil volume? Can someone explain this?