Some of our chocolates we make ourselves (How Chocolate is Made) while others we contract to other production facilities that have particular equipment we'd like to use to make the chocolate. The most advanced conch machines with high speed blades will do an extra fine job conching in less than 6 hours - anymore then that you can almost over conch. If we run conching on our production of granite rollers we found about 72 hours to be the right conch time. The conch time ultimately isn't as important as the particle size of the sugar in the chocolate or the particle size of the cacao. Too small of a particle size the chocolate will cloy while too big it will feel gritty. The final result of all of these steps are closely guarded secrets in the chocolate industry and differ from recipe to recipe.