13. The apparatus of claim 12 , wherein the computer readable instructions, when executed, cause the apparatus to adapt the acoustic model to generate an updated acoustic model based on updating statistical representations of the phonemes from speech input of the user speaking the adaptation sentence.
13. The apparatus of claim 12 , wherein the computer readable instructions, when executed, cause the apparatus to adapt the acoustic model to generate an updated acoustic model based on updating statistical representations of the phonemes from speech input of the user speaking the adaptation sentence. 14. The apparatus of claim 13 , wherein the computer readable instructions, when executed, cause the apparatus to determine an updated acoustic model gain distribution based on the phonemes of the acoustic model and phonemes of the updated acoustic model.