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| Film Recorder of Mrs von Madaler |
It is very rare indeed for a woman to feature in the patent history of motion picture sound, and so the work of Mrs Katharina von Madaler deserves an honourable mention. She was one of the many early inventors who realised the enormous advantage of recording sound on the same piece of film as the picture, and produced some devilish devices for doing this. For recording she employed a lightweight rotary cutting wheel attached to the diaphragm of a gramophone recording mechanism of the pre electric period. The cutting wheel pressed against the film edge tracing a wavy path as it made a profile of the sound wave created by the vibrating diaphragm. In her patent granted in 1911, Mrs von Madaler stated that "the cutting of the sound waves may be done simultaneously with the taking of the pictures, or after the pictures have been developed". Such a recording could be made on both film edges if required. Reproduction was accomplished by means of a gramophone sound box whose weight held a flat ended stylus or needle against the film edge. There is no record of anybody using this device, other than Mrs von Madaler herself. In the same patent was another of her bright ideas, this time for copying a gramophone record onto film. A gramophone sound box was adapted to hold a thin platinum wire which was heater to a dull red by a small battery. Sound waves generated by playing a record caused the platinum wire to vibrate and copy the sound by burning or melting the film edge. The temperature of the wire had to be very accurately controlled, so that the film was suitably indented without the celluloid actually catching fire! Quite a difficult feat with the highly inflammable nitrate-based film stock used at the time. Another patent was granted to Ferdinand and Arthur Madaler in 1926, relating to "a combined sound and picture record made by recording the sound simultaneously with the Kinematograph exposure on the surface of the celluloid film (preferable near the edge) by direct action of the stylus. A smooth sound groove, either hill and dale or zig-zag (lateral) cut, is impressed on the film without the necessity of any heating or preparatory treatment on the film". Fortunately at that time RCA and Western Electric had other ideas.
JOHN ALDRED