CDI's GeoEAR acoustic amplifier system allows a listener to hear extremely faint sounds at great distances using a geophone probe which is either inserted into the soil or placed in direct contact with the pipeline.
The GeoEAR has the ability to amplify the sound of an approaching pipeline pig's cups striking welds of a pipeline to an easily discernable level and under normal circumstances a pig can be heard approaching for miles.
The SPY-PHONE allows you to listen to any internal pipeline travelers in motion. It is not a geophone. The SPY-PHONE Pick-up Sensor covers a wide range of frequencies from 1 Hz to 20 KHz.
The SPY PHONE also allows the user to set and restrict multiple frequency ranges. The versatile Pickup Sensor, which comes with a 3" contact spike, can also be magnetically attached directly to exposed valves or pipes