Near my home there’s an old concrete bridge from the 1960’s. The bridge is ugly and nearly collapsing due to some structural errors made back in the day, but it’s still in heavy use and an important traffic vein. When you walk under it you can hear the cars above driving over an expansion joint. Those etheric bumps sound like heartbeats of an urban city. Or perhaps – as there is no regular pattern – they are last struggling heartbeats of the dying bridge.
I recorded this in Mid/Side stereo with Rhøde NTG3 and Ambient ATE208 into Sound Devices 702.