12. Engine without Acceleration

This audio begins with the gradually increasing sound of an engine, indicating that a car or automobile is idly running. The steady hum of the engine remains constant, without any acceleration or revving, suggesting the vehicle is at a standstill. There seems to be no changes in the engine's rhythm, representing a perfectly functioning, well-maintained engine of a car. The listener can almost visualize the car, parked, perhaps in a garage or driveway, its engine purring smoothly. The audio ends with the engine's sound gradually decreasing, signifying the car being turned off.