What happens if there are conflicting opinions on a specific paper under review?
I'm sure YMMV, but there is usually an Associate Editor (a member of the Board to whom the paper was assigned) that will make a recommendation to the Editor based on the reviews. The conversation you refer to usually takes place between the two of them. If an additional review is needed to decide, it can be requested. The rest of the Board is usually not involved (they have their own assignments to worry about). As an author you may or may not know who the Associate Editor assigned to your paper is.