The Fidelity Grandmaster Voice is a Decorator Challenger with no legs. They both have the electronics and program of the Fidelity Chess Challenger Advanced Voice (or Fidelity Sensory Voice). The Grandmaster Voice came first in late 1980 and my one speaks German. The Decorator Challenger arrived in 1981 and speaks English. The Decorator has a stronger, heavier frame, the Grandmaster Voice a wooden inset holding the display and keypad.
Both these machines are very rare. I do not know how many of each were made.