In this audio titled "Ventilation", one can vividly hear the pulsing heartbeat of a city, referred to as "stadt" in German. The audio kicks off by immersing listeners into the urban soundscape, characterized by a constant undercurrent of city noise, or "rauschen". It's a common echo of city life, with the distant hum of traffic, rustling of leaves, and indistinct chatter of pedestrians. But the predominant sound that sets the theme for this audio is the relentless drone of a ventilation system. This is not a high-pitched whining of a small fan, but the low, powerful hum of a large-scale urban ventilation unit. It's a sound that is omnipresent in the cityscape, yet often unnoticed until it's singled out like in this recording. The sound is both monotonous and rhythmic, underpinning the whole city's breath. Adding depth to this urban soundscape is the subtler elements of field recording.