Source : Webster's Revised Unabridged Dictionary (1913)

Orthoepist \Or"tho*["e]*pist\, n.
   One who is skilled in ortho["e]py.

Source : WordNet®

orthoepist
     n : a practitioner of orthoepy (especially one of the 17th or
         18th century scholars who proposed to reform English
         spelling so it would reflect pronunciation more closely)