A conversation detector and detection method is based on voice band energy detection. The detector is formed of a signal preconditioner, a comparator and an analysis unit. The comparator generates signal pulses reduced in resolution and sample rate (e.g., single bit data) and indicative of energy level and/or duration of activity detected in subject audio signals. The analysis unit determines from the generated signal pulses whether a conversation exists in the subject audio signal. The detector is also able to adapt to environmental noise change, automatically calibrate and operate in low power consumption mode.