This Device Diagnoses a Broken Machine by Sound. Really.This new tech troubleshoots by listening in.

When a machine is in prime working order, its parts hum in literal harmony. And when that hum turns to whirring or clicking? That's what Augury is for. The Israel- and New York–based startup's device can listen to any machine -- from a jet engine to a household appliance -- and identify what's wrong, or even predict what'll break next.

Here's how it works: Augury's ultrasonic sensor plugs into a smartphone. (The company provides it for free; it charges only for usage.) A technician -- someone at your company, say, or the repair person you called -- places the device on a machine; audio data is relayed to Augury's servers, and a diagnosis is made. Then the fixing can begin.