I know there's a bunch of you here, so I'm hoping for some insight. We are trying without success to replicate this experiment: http://www.youtube.com/watch?v=mODqQvlrgIQ
We have it set up just like in the video, and are playing mp3s of Sine waves from a Macbook, through a cable coming out of the headphone jack directly into the rca input on the back of a Polk Audio PSW10. Tried 2 different camcorders.
I have some theories (not in the scientific sense of the word) as to why it's not working.
1. The subwoofer I'm using is rated down to 35Hz, so even though I'm playing a 24Hz Sine wave through it, all I'm really getting is speaker excursions and not that actual frequency.
2. It's not a true Sine wave generator, just an mp3 of the Sine wave.
3. In order to match the frame rate of the Camcorder, I might need something more specific than a whole number frequency. Does such a thing exist - i.e. 24.5 Hz? In the video he has a dial (and probably an expensive Sine wave generator) to tune to exactly the right frequency.
4. The newer camcorder supposedly records at 60 "interlaced" FPS (tried 60Hz, got nothing), so that would negate the effect we are shooting for.
5. I'm not Bill Nye
Any thoughts, help, suggestions will be gladly welcomed!