1. A process of operating a sound recognition sensor comprising: (a) receiving analog sound signals in signal trigger logic that is maintained in a powered up active mode while maintaining other circuitry of the sensor in a low power mode; (b) powering up normally powered down parallel analog channels of the sensor in response to a first trigger signal indicating the signal trigger logic receiving analog sound signals greater than a reference; (c) extracting a first frame based sparse feature from the received analog sound signals in one analog channel; (d) extracting a second frame based sparse feature, different from the first frame based sparse feature, from the received analog sound signals in a another analog channel simultaneously with the extracting a first frame based sparse feature; (e) producing an event trigger signal from event trigger logic in response to at least one of the extracted features from the channels indicating a starting point; (f) powering up normally powered down classifier circuitry in response to the event trigger signal; and (g) performing sound recognition on the received sound signals in the classifier circuitry based on the received analog sound signals.