Some basic questions - i7 or Xeon E5?

Dual Xeons are a complete waste of money for 95% of studios.
a Xeon and a desktop processor are the exact same product.

the only reason to go Xeon on a single processor board is to jump to 10/12 core and you had better buy one of the higher GHz Xeons or its going to be slower than the 4930K.

if you over clock the 4930K a Xeon even with 12 cores would be hard pressed to keep up.
a big plus 1 for scanUK
or Daw plus in Germany.

titan is clueless about audio