As far as the "sound theory", all the videos have the same sound. The ones where I walk up to the radar gun (99, 103, 104, 105, 107), and the ones that I don't (105, 108 ).
Keep in mind, I am using a Kodak Digital Camera to record the videos. The sound or video is not going to be clear.
The guy on the video with the annoying cameraman does have a nice serve. It would have been nice if the cameraman wasn't such a goofball. I can't really tell how fast he is serving, but on the first serve it looks very fast. Too many foot faults though.
Roger Federer Pro Staff 97 Play test video