10. A speech recognition system comprising: A processor executing an application for: prompting a user to speak a first utterance, the first utterance comprising at least one phrase; in response to a determination that a first confidence value representing an expected accuracy of a speech recognition operation on the first utterance is less than a threshold value, prompting the user to speak a second utterance, wherein the second utterance comprises the at least one phrase associated with the first utterance; and recording the first and second utterances; a difference engine for processing the first and second utterances to identify a plurality of acoustic differences between first and second utterances; a speech recognition engine for: performing speech recognition on the first utterance and generating a first recognition result, wherein the first recognition result comprises the first confidence value; and performing speech recognition on the second utterance and generating a second recognition result, wherein the second recognition result comprises a second confidence value a compensation controller for compensating the speech recognition system by adjusting a plurality of adjustable parameters to compensate for the plurality of acoustic differences; wherein the speech recognition engine further processes the first and/or the second user utterances by performing compensated speech recognition of the first and/or the second user utterances, wherein the performing compensated speech recognition comprises: performing speech recognition on a selected one of the first user utterance and the second user utterance and generating a compensated speech recognition result for the selected utterance using the compensated speech recognition system, wherein the first user utterance is selected when the first confidence value is higher than the second confidence value, and wherein the second user utterance is selected when the second confidence value is higher than the first confidence value; or performing speech recognition on the first user utterance to generate a first compensated result having a first compensated confidence value using the compensated speech recognition system, performing speech recognition on the second user utterance to generate a second compensated result having a second compensated confidence value using the compensated speech recognition system, selecting the first compensated result as the compensated speech recognition result when the first compensated confidence value is greater than the second compensated confidence value, and selecting the second compensated result as the compensated speech recognition result when the second compensated confidence value is greater than the first compensated confidence value.
10. A speech recognition system comprising: A processor executing an application for: prompting a user to speak a first utterance, the first utterance comprising at least one phrase; in response to a determination that a first confidence value representing an expected accuracy of a speech recognition operation on the first utterance is less than a threshold value, prompting the user to speak a second utterance, wherein the second utterance comprises the at least one phrase associated with the first utterance; and recording the first and second utterances; a difference engine for processing the first and second utterances to identify a plurality of acoustic differences between first and second utterances; a speech recognition engine for: performing speech recognition on the first utterance and generating a first recognition result, wherein the first recognition result comprises the first confidence value; and performing speech recognition on the second utterance and generating a second recognition result, wherein the second recognition result comprises a second confidence value a compensation controller for compensating the speech recognition system by adjusting a plurality of adjustable parameters to compensate for the plurality of acoustic differences; wherein the speech recognition engine further processes the first and/or the second user utterances by performing compensated speech recognition of the first and/or the second user utterances, wherein the performing compensated speech recognition comprises: performing speech recognition on a selected one of the first user utterance and the second user utterance and generating a compensated speech recognition result for the selected utterance using the compensated speech recognition system, wherein the first user utterance is selected when the first confidence value is higher than the second confidence value, and wherein the second user utterance is selected when the second confidence value is higher than the first confidence value; or performing speech recognition on the first user utterance to generate a first compensated result having a first compensated confidence value using the compensated speech recognition system, performing speech recognition on the second user utterance to generate a second compensated result having a second compensated confidence value using the compensated speech recognition system, selecting the first compensated result as the compensated speech recognition result when the first compensated confidence value is greater than the second compensated confidence value, and selecting the second compensated result as the compensated speech recognition result when the second compensated confidence value is greater than the first compensated confidence value. 11. A system according to claim 10 wherein: said speech recognition engine comprises an acoustic model with the plurality of adjustable parameters; the difference engine matches the at least one of the plurality of acoustic differences to a matched adjustable parameter of the plurality of adjustable parameters; and the compensation controller adjusts the acoustic model by varying the matched adjustable parameter to reflect the at least one of the plurality of acoustic differences.