17. The speech coding apparatus as claimed in claim 16, further comprising the step of respectively splitting the prototypes into bands wherein each band contains the mean and the variance values of one or more elements of the particular prototype having substantially similar Gaussian density distributions with respect to each other.
17. The speech coding apparatus as claimed in claim 16, further comprising the step of respectively splitting the prototypes into bands wherein each band contains the mean and the variance values of one or more elements of the particular prototype having substantially similar Gaussian density distributions with respect to each other. 18. The speech coding apparatus as claimed in claim 17, wherein each prototype has approximately 39 elements whereby the elements may be grouped into approximately 20 bands.