pay attention to these tips
-subtract cone volume and magnet volume of 2 driver from vrc
-add cone volume of 2 driver to vtc
-put 2 driver in the driver arrangement menu
-in the spl screen, tools menu,directivity, reponse put 69 degree
divide all the quotes by 2,54 you get the inches.
divided all the quotes by 2,54 , get the integer value and now substract it to the quote divided by 2,54. now convert this value in your crazy imperial fraction.