[quote author=SidneyR link=topic=873.msg10322#msg10322 date=1385274990]
Dear Professor,

This is very helpful stuff.  I'm curious though - when I downloaded
the Doppler Effect program, there was no ear, and I couldn't hear any
sound.  Is there supposed to be an ear in the download version?

Many thanks,
SidneyReilly

[/quote]

Yes. There is an ear in the simulation. However, I do not know why it was missing in the downloaded version.
It is fixed now.
Please download it again.