4. The method of claim 1 , further comprising generating a second final sequence of audio units corresponding to a second received audio input, wherein the key phrase recognition model further comprises a second transition from the single start state based rejection model to a second key phrase model, wherein the second key phrase model comprises a plurality of second states having second transitions therebetween, the plurality of second states including a second final state of the second key phrase model, wherein the plurality of second states of the second key phrase model correspond to the second final sequence of audio units.
5. The method of claim 4 , wherein the second received audio input represents a second user defined key phrase different than the user defined key phrase.