1. A method of recognizing a received phoneme using a stored plurality of phoneme classes, each of the plurality of phoneme classes comprising class phonemes, the method comprising: (A) training the class phonemes, the training comprising, for each class phoneme: (1) determining a phoneme vector as a time-frequency representation of the class phoneme; (2) dividing the phoneme vector into phoneme segments; (3) assigning each phoneme segment into a plurality of phoneme parameters; (4) expanding each phoneme segment and plurality of phoneme parameters into an expanded stored-phoneme vector with expanded vector parameters; (5) transforming the expanded stored-phoneme vector into an orthogonal form using singular-value decomposition wherein: &lsqb;x 1 x 2... x m &equals;&lsqb;u 1 u 2... u m &lsqb;&Lgr;V t, where x k is a k th acoustic vector for a corresponding stored phoneme, u k is the corresponding orthogonal vector and &Lgr; and V are diagonal and unitary matrices, respectively; and (B) recognizing the received phoneme by: (1) receiving an analog acoustic signal; (2) converting the analog acoustic signal into a digital signal; (3) determining a received-signal vector as a time-frequency representation of the received digital signal; (4) dividing the received-signal vector into received-signal segments; (5) assigning each received-signal segment into a plurality of received-signal parameters; (6) expanding each received-signal segment and plurality of received-signal parameters into an expanded received-signal vector, (7) transforming the expanded received-signal vector into an orthogonal form using singular-value decomposition wherein: &lsqb;y k &rsqb;&equals;&lsqb;z k &rsqb; &Lgr;V t, where y k is a k th acoustic vector for a corresponding received phoneme, z k is the corresponding orthogonal vector and &Lgr; and V are diagonal and unitary matrices, respectively; (8) determining a first distance associated with the orthogonal form of the expanded received-signal vector and a second distance associated respectively with each orthogonal form of the expanded stored-phoneme vectors; and (9) recognizing the received phoneme according to a comparison of the first distance with the second distance.