With this in mind, I'll continue. The Spectrograms I'm using were created by Cool Edit , which is available on the web. The low-cost program performs flawlessly, and has aided my research immensely. If a line is ascending, the tone of the call is rising. The horizontal scale is time in seconds, and you can see the total time of a particular sample in the data box below the image.
Sound volume is indicated by the brightness and color of the image.
In general, the yellower the image, the louder it is. When people talk to each other, the talker thinks of the right words to convey his idea, translates those thoughts to vocabulary the recipient can understand best, encodes the words to sounds and produces corresponding sound waves which the recipient can hear. When we hear music, on the other hand, we experience a more direct change in our feelings . Good rock and roll energizes, and other music can irritate us. It's possible that birds are communicating vocally in the same way that we communicate with music.