— Sounds from Bluebird Hill

*** The 2019 Recording Season is over;  I hope to resume again next spring ***


This page is a personal project based on work I did at the Ohio Agricultural Research and Development Center (OARDC) a decade ago attempting to relate recorded audio samples to the health of the agricultural ecosystem.

My recorder is in our yard across the lane from our house, between the old milk house and the red raspberry patch…an appropriate location for the Raspberry Pi controller.  Every thirty minutes the controller makes a thirty second recording of the sound. There is a brief description of my recording system and the software on a subsequent page.

While our farm is somewhat secluded, we are less than half of a mile from one of the busier thoroughfares through our rural county and our township road is less than five hundred feet from the recorder.  So while at various times of the year the recordings are dominated by the sounds of frogs and toads, birds, and insects there is a near constant background sound of motors and vehicles.  And of course, you will occasionally hear us mowing, weed eating, rototilling the garden, etc.  You may hear aircraft passing overhead, gunshots from our neighbors target shooting, and any number of other sounds.  Be alert to gentle S-shaped curves in the Audio Spectrogram indicating a Doppler shifted sound.

The audio and spectrograms shown below will be updated a few minutes past the hour/half hour.  Always refresh the page to get the latest information. The audio spectrogram gives a picture of how the frequency (vertical scale) and amplitude (brighter color implies louder sound) vary with time through the thirty second recording.  You can listen to the audio associated with the spectrogram using the player below the graphic.


The power spectral density (PSD) graph below on the left is a composite of the amplitude and frequency components of the spectrogram shown above.  The graphic on the right is a summary of the PSD results over the course of the day with a new slice being added at the hour/half hour update totaling 48 slices for the complete day.  The bigger graphic at the bottom extends that process to the entire month. The monthly spectrogram can have up to 1488 slices.  The daily and monthly spectrograms are useful in looking for daily rhythms, longer term patterns, and other interesting features.