This sound recording was made in August 1998 in South-Central Arizona. The original recording was stored on DAT at 48 ksps sample rate. The microphone was a Sennheiser MKH70 shotgun and the distance to the bird varied between 20 -30 feet. The recording has been edited to remove gaps of silence to shrink the file size. Typically there is 10-15 seconds between song bursts. The Cassin's song has both medium range frequencies and high frequencies. The FFT (Fast Fourier Transform) plot below shows the dramatic spread between the frequencies of a part of one burst that was selected for its high frequency content. Amplitude is represented by the vertical axis and frequency is represented on the horizontal axis. Note that in this small song fragment only 0.22 sec long, the major frequency content is around 9,500 Hz with some frequency content at 18,000 Hz.It is possible to pick other sections of the song that range between 2,000 Hz and 8,000 Hz.
FFT Plot of Cassin's Sparrow Song Fragment Selected to Emphasize the High Frequency Content
download mpeg3 recording (cassins.mp3)
download mpeg3 decoder
Copyright Greg Clark, 1999