1. A system comprising a computing device that includes a processor and a memory, the memory storing instructions executable by the processor to: perform a first convolution that includes convolving a spoken utterance with a second acoustic impulse response that is based on acoustic characteristics of a vehicle cabin; receive output of a second convolution, of vehicle sounds retrieved from an electronic sound database with a first acoustic impulse response that is based on acoustic characteristics of a room, from a speaker in the room while recording the spoken utterance to generate output sounds that include the spoken utterance according to the first convolution; and generate a speech file from the output sounds.
4. The system of claim 1 , further comprising a microphone for receiving the at least one spoken utterance, wherein the at least one spoken utterance is provided to a microphone and converted to a digital sound file that is provided to the computing device.