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.
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. 15. The apparatus of claim 14 , wherein the computer readable instructions, when executed, cause the apparatus to determine that a similarity measure based on the updated acoustic model gain distribution satisfies a stopping criterion to end adaptation of the updated acoustic model.