You might try to find the book "The descendants of Jacob Schoff"; who came to Boston in 1752 and settled in Ashburnham in 1757 : with an account of the German immigration into colonial New England Author: Schoff, Wilfred H. 1874-1932. City of Publication: Philadelphia Publisher: J. McGarrigle Date: 1910 It may be available through loan from your local library or inter-library loan. It seems to be a very good source of information on the Schoaf/Schoff/Shoff family line.
Good luck. Charles Reeves Shaw, a decendant of Michael Schoaf whose father Friedrick may be a child of Jacob Schoaf.