A method for customizing speech-recognition dictionaries for different smart-home environments may include generating, at a smart-home device mounted in an enclosure, an acoustic impulse response for the enclosure. The method may also include receiving, by the smart-home device, an audio signal captured in the enclosure. The method may additionally include performing, by the smart-home device, a speech-recognition process on the audio signal using a second speech dictionary generated by convolving the acoustic impulse response with a first speech dictionary.