I began hearing a low hum in my house at night sometime in November.
It was constant, below conversation frequency, felt more than heard — in the chest, in the back teeth, in the sinus. I thought it was mechanical. Furnace, water heater, something cycling that shouldn't be.
I called a repairman. He checked everything and found nothing unusual. He said he could hear the hum too. He couldn't identify the source.
My neighbor two doors down knocked on my door in December. She asked if I could hear it. She said she'd been hearing it for three weeks. Her husband heard it. Her kids heard it. She'd thought it was her own house.
We compared notes. The hum was the same — same frequency, same quality, same nighttime schedule. It started around midnight and stopped around 4 AM. It wasn't her house or mine. It was both. It was, we realized when we asked around, every house on the block.
We hired an acoustical engineer. She spent two nights with equipment set up throughout the neighborhood. She found the hum in her readings — she could measure it, quantify it, confirm it was real. She could not find a source. She said the readings suggested the origin point was underground, but she found no structure beneath the neighborhood that could be producing it.
The hum continued through January. In February, it changed.
Not louder. Different in quality — a new element in it, a variation, almost structured. The acoustical engineer came back. She listened to the new recordings for a long time. She said, carefully, that the variation was patterned. She said that if she were being unscientific she would say it sounded like something adjusting. Like something that had been broadcasting a carrier signal was now beginning to encode information on top of it.
She said she didn't know what information.
She packed her equipment and left and did not respond to subsequent emails.
The hum is still there. It's been changing slowly all spring. Last week one of my neighbors said she'd started understanding it.
She said that was probably bad.
She moved the following weekend.