Abstract: An audio recorder with retroactive storage capability operates under control of a sound responsive switch to enter signals representative of the instantaneous amplitude of sound signals received by a microphone into a first-in first-out memory. When the memory is filled, digital signals representative of newly recorded sound supplant the oldest signals in the memory. An operator listening to the sound may retroactively capture signals representative of the most recently occurring sounds against erasure by depressing a pushbutton. Circuitry responsive to the resulting signal removes the most recently generated sound signals from the first-in first-out queue so that they may be later recalled to reproduce the sounds.