Ten different Fantasound setups were built and tested during its development. As many as several hundred designs were detailed on paper, each with different equipment combinations. The first set-up that was constructed, the Mark I system, used a left, center and right speaker placed across the stage plus one in each corner at the back of the auditorium. It used two sound channels, one directed at the stage center (or "screen") speaker, while the second could travel around the remaining four across the room smoothly using a manually controlled four-circuit panpot. The following Mark II configuration used a third sound channel and three additional speakers, one placed on each side wall of the house and a third placed in the middle of the ceiling, all with a manual six-circuit panpot. By the time the Mark II system was devised, the control of the sound system was too complex for a single operator. To solve that difficulty, the Mark III system was developed to study the effects of a pilot tone-control track. The configuration was a single-channel Togad expander, controlled by either an oscillator or a tone track.

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