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Mod-III Sensurround was a further refinement of the system to allow more control over level, timbre and placement of effects.

Instead of a simple wide-range rumble that could be felt and heard, Mod-III used more narrow band extended low frequency effects in the 16 – 25 Hz range, in addition to the higher frequency program sounds and surround-sound effect.

Thus, scenes could have dialogue and other audio at standard levels, plus the effect of movement from the infrasonic rumble, creating sensations that had not been possible in earlier Sensurround films.

Mod-III Sensurround was used in Battlestar Galactica in 1978.