9. The apparatus according to claim 6 further including a register for storing digital data, wherein said data stored therein represent the average signal level computed by said binary adder in the absence of speech, and wherein said stored data establish said predetermined signal level.
6. In a speech recognition system, an apparatus for storing speech parameters, said apparatus comprising: transducer means responsive to acoustic energy for transforming said acoustic energy into analog electric signals, wherein said acoustic energy comprises voiced speech, unvoiced speech and background noise; signal processing means for converting said analog signals to substantially equivalent forms of speech parameters and for sampling said speech parameters at a predetermined sampling rate; first storage means coupled to said signal processing means for temporarily storing a plurality of samples of said speech parameters from said signal processing means; a binary adder coupled to said signal processing means for computing the average signal level of samples of said speech parameters from said signal processing means during predetermined periods of time; second storage means coupled to said first storage means for receiving speech parameters transferred from said first storage means; means coupled to said second storage means for generating sequential addresses corresponding to individual storage locations of said second storage means to permit storage of said transferred speech parameters therein; and means coupled to said address generating means and to said binary adder for resetting said generating means to a reference starting address when the average signal level computed during any of said predetermined periods of time fails to exceed a predetermined signal level.