This bird's song starts each day in the afternoon, and he thrills us until the sun goes down. Although the sound is very full and loud, I can't seem to spot the singer. Does anyone know what kind of bird this could be? We have never heard him before, in all the years we have lived here in northern California.
I found it interesting to look at the wave forms of this song, using Audacity (a free voice editing application). Look at how clear each tweet is, even the warbley part at the right. Each time the bird produced this sound, the pattern was virtually the same. There are some sites online where you can identify birds by comparing these wave forms. But so far, I haven't found my little friend.