Take a look at my soffits

I am posting this to make sure I have the right idea for soffit placement. I will be following John's construction method... I just want to make sure my setup and design are correct. My room is 31' 6" x 18' 3" Here is the picture... The speakers will be Adam S5V-A

the 60 degrees angle is correct - the speakers should be at 30 degrees.