– According to Wade and Deutsch term was used to describe that two ears are involved in human hearing
– Until the 1970’s binaural wasn’t used to describe signals that have been modified by the human body and would therefore correspond to the signals at the eardrum of a listener. Till 70s terms binaural and stereophonic were used mostly as synonyms.
- Fletcher, in 1920’s have been the first one to use the term binaural for a recording technique and Hamme & Snow distinguished as first between binaural and stereophonic pick-up. They considered binaural when the signals (acquired with a dummy head) were fully reproduced by the headphones
- The terms “dummy head” were used in 1920’s
- Nowadays binaural technology is used to describe two signals reproduced in such a way that the signals that would be found at the eardrum of a listener, after being modified by a human body.
“Binaural broadcasting” – an article written by Doolittle in 1925, no model of a head was used for broadcasting. - Berlin opera house in 1925: binaural transmission
- 1927, W. Barlett Jones: a patent for devices to capture, record and reproduce “binaural” signals. It was a type of “artificial head” represented be a sphere.
- 1930’s, based on Fletcher’s experience with his binaural hearing aid (the binaural telephone system) and the fact that having two ears provides higher fidelity in a relation to sound perception, the manikin “Oscar” was invented. The wax figure that had microphones mounted on the cheeks, just in front of the ears. This experiment proved that signals with higher fidelity could be achieved by reproducing the human by way of a manikin.
- Fletcher thought that the use of two mic’s could create a spatial sound effect
- The numbers of recording were taken with Philadelphia Symphony Orchestra (in cooperation with Mr. Stokowski). The binaural signals obtained with “Oscar” were compared with the live listening experience.
- At 40s’ the main challenge of stereophony was maintaining phase information between two channels. This was resolved in mid 40s when magnetic tape recorders became more available. Other problems at this time were the limited frequency response and dynamic range of recording equipment
- After World War II in the Netherlands started a transmission of a binaural radio program using a manikin of De Boer and Vermeulen.
- Bell Labs developed “Oscar II” in 40s’ which had the microphones placed in the ears (5 mm distance outside the cave conchae).
- In 50s’, Andre Charlin, a French recording engineer, presented his “head” – tete Charlin. It was a balloon made of leather
- In 1955 Shoeps presented a microphone made of an aluminium sphere 20 cm in diameter with two omni microphones placed on the circumference (Kugelflächenmikrophon)
Source:
1. Stephen Paul – Binaural Recording Technology: A Historical Review and Possible Future Developments
2. Jens Blauert – The technology of binaural understanding
