Act 1

Tuba Echo from Nathan Kraft on Vimeo.

Act 2
I decided to use the measured distance to find the speed of sound. You might want to do this backwards, ie use the speed of sound to find the distance. So just switch acts 2 and 3. It might be helpful to use a metronome to figure out how many beats per second there are. This will tell you how long it takes for the sound to travel out and back.
You can also find this location on Google Earth and measure it yourself: Latitude (40°40'55.66"N), Longitude (76°12'40.66"W).
David Lippman was nice enough to create this visual of the soundwave for me. Thanks David! You could also use this to figure out the time it takes for the sound to travel.

Act 3
Temperature does have some affect on the actual speed of sound. You can use this site to calculate it given the temperature. It was about 60 degrees Fahrenheit when we filmed this.