Better vocoders are coming

The present state of the art and possible future trends in vocoder development are discussed both on the basis of further improvement to standard techniques and with reference to new approaches Synthetic speech systems which are designed to accomplish economies in transmission, or to meet special military needs, traditionally have involved some degree of degradation in the process whenever they involve bandwidth compression. If speech information can be successfully concentrated into narrower bands, the savings in channel capacity accruing from this procedure would be of great economic importance in reducing future capital investment in transmission systems.