I will be playing with it over the next few days as I find ways to make a cheap T-post driver quieter.
If you ever spent much time operating one of these beauties (T post drivers) then you know they can leave your ears ringing if you don't wear hearing protection, especially if the ground is dry or rocky.
The protocol is simple. Suspend the driver horizontally but running strings through the handle. Tap the end of the driver where the T posts impact. For convenience, I am tapping the outside of the surface rather than the inside, a difference of a 1/4 inch or so.
|Log scale along horizontal axis.|
I do not know if the instrument is reporting pressure or energy. An increase in 10 dBa indicates a ten-fold increase. A 40 dBa increase is a relative increase of 10,000.
A scientific study would use an instrumented and calibrated hammer to measure the inputs to the system.
Various modifications will be made to the T-post driver and I will re-test. Our metric will be the height of the 1000-to-2500 Hz region and 3400 Hz relative to the heights of the 5000-to-10,000 Hz region.
Secondarily, to see who quickly we can damp down or dissipate the duration of the noise levels.