A voice controlled system includes a microphone for receiving voice commands and for converting each voice command to an electrical output; a filter system connected to receive the electrical outputs of the microphone and to produce for each voice command a first output corresponding to the high-frequency component of the voice command, and a second output corresponding to the low-frequency component of the voice command; and a processor for processing the first and second outputs of the filter system, and for outputting, for each voice command, a first electrical signal when the low-frequency component precedes the high-frequency component in the respective voice command, and a second electrical signal when the high-frequency component precedes the low-frequency component in the respective voice command. The voice command is determined to be a "Yes" command when the low-frequency component precedes the high-frequency component; a "Stop" command when the high-frequency precedes the low-frequency component and a "No" command when the high-frequency component is below a predetermined threshold.