RESEARCH
PEOPLE
PUBLICATIONS
GIVING


UNDERSTANDING SPEECH
READING
SPEECH TECHNOLOGY
Play in AIFF format (22kHz, 127K) - or - Play in AU format (8kHz, 44K)
This sample sound file (from Aug. 1958) contains three versions of "Never kill a snake."
(a) by transmission
(b) by reflection (a hand copy with fine structure preserved)
(c) by reflection (a hand copy which has been simplified and schematized).
By Transmission
The Pattern Playback can convert spectrograms into sound. In one form of operation (transmission), a negative is made from a sound spectrogram so that regions occupied by sound are now transparent. Modulated light passed through these regions is picked up by the light collector and amplified.
By Reflection
To hand-copy a spectrogram, a clear sheet of plastic is placed over the spectrogram. Those regions that contain sound in the original are copied over with white paint. The light collector on the Pattern Playback now picks up only those frequencies that are reflected by the white paint.

