A Speech Synthesizer

“Standardized speech” constructed from building blocks called speech modules has been described; it was synthesized by piecing together bits of magnetic tape containing recorded speech sounds. An electromagnetic device, a “speech module synthesizer,” is described here which performs the synthesis automatically. When buttons on a keyboard are pressed, a sequence of corresponding speech modules are automatically recorded on tape exactly in tandem. The modules are selected from a group “stored” on a rotating magnetic drum. The pressing of a button causes an electrical signal corresponding to a module to be reproduced—the electrical switching is so arranged that only one complete module is reproduced for a single button‐pressing. This electrical signal is amplified, biased, and then fed into a constantly rotating head which makes contact with stationary magnetic tape and records the signal on it. A 10‐kc signal superposed on each stored speech module controls an electromagnetic clutch which (a) measures the length of the recording accurately, and (b) advances the tape at the completion of the recording by the correct amount so that the next recording forms a connected sequence with it. The same module may be used any number of times and in combination with different stored modules, thereby introducing wider experimental control in standardized speech studies. The principle of this type of device could be applied to other classes of problems involving communication of information, as the conversion into speech of typing or of electronically‐read printed matter.