Abstract: The AGC circuit and method especially applicable in circuits where fast response and stability of the system is necessary, such as where input signals are speech patterns. A gain feedback loop repeatedly adapts the gain and a long term average energy E.sub.mean of the output signal until it approaches a predetermined level. In each pass through the gain feedback loop the long term average energy E.sub.mean is increased by a gain compensation parameter directly proportional to a gain change, thereby rapidly adapting the long term average energy E.sub.mean to converge to the predetermined level.